diff --git a/core/libs/prx/libSceUlt/Export.cpp b/core/libs/prx/libSceUlt/Export.cpp
index a9fc644954..506333c24e 100644
--- a/core/libs/prx/libSceUlt/Export.cpp
+++ b/core/libs/prx/libSceUlt/Export.cpp
@@ -1,3 +1,4 @@
+#include <algorithm>
 #include <atomic>
 #include <condition_variable>
 #include <cstddef>
@@ -123,6 +124,7 @@ int APS5_VABI sceUltInitialize() {
 
 int APS5_VABI sceUltFinalize() {
     std::vector<std::shared_ptr<UltSemaphoreState>> semaphores;
+    std::vector<std::shared_ptr<UltMutexState>> mutexes;
     {
         std::lock_guard<std::mutex> lock(gMutex);
         if (!gUlthreads.empty()) {
@@ -136,6 +138,13 @@ int APS5_VABI sceUltFinalize() {
             semaphores.push_back(state);
         }
         gSemaphores.clear();
+        mutexes.reserve(gMutexes.size());
+        for (auto& entry : gMutexes) {
+            auto& state = entry.second;
+            std::lock_guard<std::mutex> stateLock(state->_mutex);
+            state->_alive = false;
+            mutexes.push_back(state);
+        }
         gMutexes.clear();
         gResourcePools.clear();
         for (auto& entry : gQueues) {
@@ -152,6 +161,9 @@ int APS5_VABI sceUltFinalize() {
     for (const auto& state : semaphores) {
         state->_available.notify_all();
     }
+    for (const auto& state : mutexes) {
+        state->_available.notify_all();
+    }
     return ULT_OK;
 }
 
@@ -172,15 +184,38 @@ int APS5_VABI sceUltMutexCreate(void* mutex, const char* name, void* waitingQueu
     }
     auto state = std::make_shared<UltMutexState>();
     state->_attribute = optParam != nullptr ? optParam->attribute : 0;
+    state->_waitingPool = waitingQueueResourcePool;
     std::lock_guard<std::mutex> lock(gMutex);
     if (waitingQueueResourcePool != nullptr && gResourcePools.find(waitingQueueResourcePool) == gResourcePools.end()) {
         return ULT_ERROR_INVALID;
     }
+    if (gMutexes.find(mutex) != gMutexes.end()) {
+        return ULT_ERROR_STATE;
+    }
     std::memset(mutex, 0, 256);
     gMutexes[mutex] = std::move(state);
     return ULT_OK;
 }
 
+int APS5_VABI sceUltMutexDestroy(void* mutex) {
+    if (mutex == nullptr) {
+        return ULT_ERROR_NULL;
+    }
+    std::lock_guard<std::mutex> lock(gMutex);
+    auto it = gMutexes.find(mutex);
+    if (it == gMutexes.end()) {
+        return ULT_ERROR_STATE;
+    }
+    auto state = it->second;
+    std::lock_guard<std::mutex> stateLock(state->_mutex);
+    if (state->_lockCount != 0 || state->_waiters != 0) {
+        return ULT_ERROR_BUSY;
+    }
+    state->_alive = false;
+    gMutexes.erase(it);
+    return ULT_OK;
+}
+
 int APS5_VABI sceUltMutexLock(void* mutex) {
     std::shared_ptr<UltMutexState> state;
     {
@@ -191,7 +226,30 @@ int APS5_VABI sceUltMutexLock(void* mutex) {
         }
         state = it->second;
     }
-    state->_mutex.lock();
+    const auto self = std::this_thread::get_id();
+    std::unique_lock<std::mutex> lock(state->_mutex);
+    if (!state->_alive) {
+        return ULT_ERROR_STATE;
+    }
+    if (state->_owner == self) {
+        ++state->_lockCount;
+        return ULT_OK;
+    }
+    ++state->_waiters;
+    try {
+        state->_available.wait(lock, [&] {
+            return !state->_alive || state->_lockCount == 0;
+        });
+    } catch (...) {
+        --state->_waiters;
+        throw;
+    }
+    --state->_waiters;
+    if (!state->_alive) {
+        return ULT_ERROR_STATE;
+    }
+    state->_owner = self;
+    state->_lockCount = 1;
     return ULT_OK;
 }
 
@@ -205,7 +263,16 @@ int APS5_VABI sceUltMutexUnlock(void* mutex) {
         }
         state = it->second;
     }
-    state->_mutex.unlock();
+    const auto self = std::this_thread::get_id();
+    std::lock_guard<std::mutex> lock(state->_mutex);
+    if (!state->_alive || state->_owner != self) {
+        return ULT_ERROR_STATE;
+    }
+    --state->_lockCount;
+    if (state->_lockCount == 0) {
+        state->_owner = {};
+        state->_available.notify_one();
+    }
     return ULT_OK;
 }
 
@@ -226,6 +293,43 @@ int APS5_VABI sceUltWaitingQueueResourcePoolCreate(void* pool, const char* name,
     return ULT_OK;
 }
 
+int APS5_VABI sceUltWaitingQueueResourcePoolDestroy(void* pool) {
+    if (pool == nullptr) {
+        return ULT_ERROR_NULL;
+    }
+    std::lock_guard<std::mutex> lock(gMutex);
+    auto it = gResourcePools.find(pool);
+    if (it == gResourcePools.end()) {
+        return ULT_ERROR_STATE;
+    }
+    for (const auto& entry : gMutexes) {
+        if (entry.second->_waitingPool == pool) {
+            std::lock_guard<std::mutex> stateLock(entry.second->_mutex);
+            if (entry.second->_waiters != 0) {
+                return ULT_ERROR_BUSY;
+            }
+        }
+    }
+    for (const auto& entry : gSemaphores) {
+        if (entry.second->_waitingPool == pool) {
+            std::lock_guard<std::mutex> stateLock(entry.second->_mutex);
+            if (entry.second->_waiters != 0) {
+                return ULT_ERROR_BUSY;
+            }
+        }
+    }
+    for (const auto& entry : gQueues) {
+        if (entry.second->_pool && entry.second->_pool->_waitingPool == pool) {
+            std::lock_guard<std::mutex> poolLock(entry.second->_pool->_mutex);
+            if (entry.second->_waiters != 0) {
+                return ULT_ERROR_BUSY;
+            }
+        }
+    }
+    gResourcePools.erase(it);
+    return ULT_OK;
+}
+
 std::uint64_t APS5_VABI sceUltQueueDataResourcePoolGetWorkAreaSize(std::uint32_t numData, std::uint64_t dataSize, std::uint32_t numQueueObject) {
     if (dataSize > UINT64_MAX - 7u) throw std::out_of_range("ULT queue data size overflow");
     const auto stride = alignUp(dataSize, 8u);
@@ -360,6 +464,7 @@ int APS5_VABI sceUltSemaphoreCreate(void* semaphore, const char* name, std::int3
     }
     auto state = std::make_shared<UltSemaphoreState>();
     state->_resources = numInitialResource;
+    state->_waitingPool = waitingQueueResourcePool;
     std::lock_guard<std::mutex> lock(gMutex);
     if (waitingQueueResourcePool != nullptr && gResourcePools.find(waitingQueueResourcePool) == gResourcePools.end()) {
         return ULT_ERROR_INVALID;
diff --git a/core/libs/prx/libSceUlt/SceUltTypes.hpp b/core/libs/prx/libSceUlt/SceUltTypes.hpp
index 0a314a9d56..995972b952 100644
--- a/core/libs/prx/libSceUlt/SceUltTypes.hpp
+++ b/core/libs/prx/libSceUlt/SceUltTypes.hpp
@@ -6,6 +6,7 @@
 #include <cstdint>
 #include <memory>
 #include <mutex>
+#include <thread>
 #include <vector>
 #include "SceTypes.hpp"
 
@@ -19,8 +20,14 @@ constexpr int ULT_ERROR_BUSY = -2139029497;
 constexpr int ULT_ERROR_AGAIN = -2139029496;
 
 struct UltMutexState {
-    std::recursive_mutex _mutex;
+    std::mutex _mutex;
+    std::condition_variable _available;
+    std::thread::id _owner{};
+    std::uint32_t _lockCount = 0;
+    std::uint32_t _waiters = 0;
+    bool _alive = true;
     std::uint32_t _attribute = 0;
+    void* _waitingPool = nullptr;
 };
 
 struct UltSemaphoreState {
@@ -29,6 +36,7 @@ struct UltSemaphoreState {
     std::int32_t _resources = 0;
     std::uint32_t _waiters = 0;
     bool _alive = true;
+    void* _waitingPool = nullptr;
 };
 
 struct UltResourcePoolState {
diff --git a/core/libs/tests/GuestUltThread.cpp b/core/libs/tests/GuestUltThread.cpp
index fdf347e64e..b076be3735 100644
--- a/core/libs/tests/GuestUltThread.cpp
+++ b/core/libs/tests/GuestUltThread.cpp
@@ -4,6 +4,7 @@
 #include <cstdlib>
 #include <cstdint>
 #include <cstring>
+#include <chrono>
 #include <thread>
 
 extern "C" {
@@ -30,6 +31,11 @@ int APS5_VABI _sceUltQueueDataResourcePoolCreate(void*, const char*, std::uint32
 int APS5_VABI _sceUltQueueCreate(void*, const char*, std::uint64_t, void*, void*, const void*, std::uint32_t);
 int APS5_VABI sceUltQueuePush(void*, const void*);
 int APS5_VABI sceUltQueuePop(void*, void*);
+int APS5_VABI sceUltMutexDestroy(void*);
+int APS5_VABI sceUltWaitingQueueResourcePoolDestroy(void*);
+int APS5_VABI sceUltSemaphoreDestroy(void*);
+int APS5_VABI sceUltQueueDestroy(void*);
+int APS5_VABI sceUltQueueDataResourcePoolDestroy(void*);
 }
 
 static constexpr int Ok = 0;
@@ -177,6 +183,34 @@ static void UnderscoredCreate() {
     std::uint64_t value = 0x1122334455667788ull, output = 0;
     CHECK(sceUltQueuePush(queue, &value) == Ok);
     CHECK(sceUltQueuePop(queue, &output) == Ok && output == value);
+    CHECK(sceUltWaitingQueueResourcePoolDestroy(nullptr) == Null);
+    CHECK(sceUltWaitingQueueResourcePoolDestroy(unknownPool) == State);
+    CHECK(sceUltMutexDestroy(nullptr) == Null);
+    CHECK(sceUltMutexLock(mutex) == Ok);
+    CHECK(sceUltMutexDestroy(mutex) == Busy);
+    std::atomic<bool> waiterStarted{false};
+    std::atomic<bool> waiterAcquired{false};
+    std::thread waiter([&] {
+        waiterStarted.store(true, std::memory_order_release);
+        CHECK(sceUltMutexLock(mutex) == Ok);
+        waiterAcquired.store(true, std::memory_order_release);
+        CHECK(sceUltMutexUnlock(mutex) == Ok);
+    });
+    while (!waiterStarted.load(std::memory_order_acquire)) std::this_thread::yield();
+    std::this_thread::sleep_for(std::chrono::milliseconds(20));
+    CHECK(!waiterAcquired.load(std::memory_order_acquire));
+    CHECK(sceUltMutexDestroy(mutex) == Busy);
+    CHECK(sceUltWaitingQueueResourcePoolDestroy(pool) == Busy);
+    CHECK(sceUltMutexUnlock(mutex) == Ok);
+    waiter.join();
+    CHECK(waiterAcquired.load(std::memory_order_acquire));
+    CHECK(sceUltWaitingQueueResourcePoolDestroy(pool) == Ok);
+    CHECK(sceUltWaitingQueueResourcePoolDestroy(pool) == State);
+    CHECK(sceUltMutexDestroy(mutex) == Ok);
+    CHECK(sceUltMutexDestroy(mutex) == State);
+    CHECK(sceUltSemaphoreDestroy(semaphore) == Ok);
+    CHECK(sceUltQueueDestroy(queue) == Ok);
+    CHECK(sceUltQueueDataResourcePoolDestroy(dataPool) == Ok);
 }
 
 int main(int argc, char** argv) {
diff --git a/docs/dev/debt/libSceUlt.md b/docs/dev/debt/libSceUlt.md
index e1fb5ff21a..3ac4a39278 100644
--- a/docs/dev/debt/libSceUlt.md
+++ b/docs/dev/debt/libSceUlt.md
@@ -9,3 +9,5 @@
 ### Functional
 
 - [libSceUlt queues](../../../core/libs/prx/libSceUlt/Export.cpp) use preallocated host storage instead of the supplied guest work area; its existing size formula and the 512-byte object layouts remain unverified. Waiting-queue pool thread limits and waiter priority ordering are not implemented. Finalization wakes blocked queue callers with `ULT_ERROR_STATE`.
+- [sceUltWaitingQueueResourcePoolDestroy](../../../core/libs/prx/libSceUlt/Export.cpp) refuses with `ULT_ERROR_BUSY` only when a thread is currently waiting on a pool-backed mutex, semaphore or queue, matching the PS5 libSceUlt disassembly (0x473a in or55417wcDk); bound but idle objects do not block pool destruction. Waiting-queue pool guest work area node accounting is not implemented.
+- [sceUltMutexDestroy](../../../core/libs/prx/libSceUlt/Export.cpp) returns `ULT_ERROR_BUSY` when the mutex is held or has waiting threads, tracked via owner and waiter counts in `UltMutexState`. Prosper (`hle_ult.cpp`) logs a destroy of a held mutex and returns `ULT_OK`; AnyPS5 returns `ULT_ERROR_BUSY` to prevent destroying active mutexes.