diff --git a/osal/usb_osal_threadx.c b/osal/usb_osal_threadx.c
new file mode 100644
index 00000000..7a36ea10
--- /dev/null
+++ b/osal/usb_osal_threadx.c
@@ -0,0 +1,294 @@
+/*
+ * Copyright (c) 2024, sakumisu
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include "usb_osal.h"
+#include "usb_errno.h"
+#include "tx_api.h"
+
+/* create bytepool in tx_application_define
+ *
+ * tx_byte_pool_create(&usb_byte_pool, "usb byte pool", memory_area, 65536);
+ */
+
+extern TX_BYTE_POOL usb_byte_pool;
+
+usb_osal_thread_t usb_osal_thread_create(const char *name, uint32_t stack_size, uint32_t prio, usb_thread_entry_t entry, void *args)
+{
+    CHAR *pointer = TX_NULL;
+    TX_THREAD *thread_ptr = TX_NULL;
+
+    tx_byte_allocate(&usb_byte_pool, (VOID **)&thread_ptr, sizeof(TX_THREAD), TX_NO_WAIT);
+
+    if (thread_ptr == TX_NULL) {
+        return NULL;
+    }
+
+    tx_byte_allocate(&usb_byte_pool, (VOID **)&pointer, stack_size, TX_NO_WAIT);
+    if (pointer == TX_NULL) {
+        return NULL;
+    }
+
+    tx_thread_create(thread_ptr, (CHAR *)name, (VOID(*)(ULONG))entry, (uintptr_t)args,
+                     pointer, stack_size,
+                     prio, prio, TX_NO_TIME_SLICE, TX_AUTO_START);
+
+    return (usb_osal_thread_t)thread_ptr;
+}
+
+void usb_osal_thread_delete(usb_osal_thread_t thread)
+{
+    TX_THREAD *thread_ptr = NULL;
+
+    if (thread == NULL) {
+        /* Call the tx_thread_identify to get the control block pointer of the
+        currently executing thread. */
+        thread_ptr = tx_thread_identify();
+
+        /* Check if the current running thread pointer is not NULL */
+        if (thread_ptr != NULL) {
+            /* Call the tx_thread_terminate to terminates the specified application
+            thread regardless of whether the thread is suspended or not. A thread
+            may call this service to terminate itself. */
+            tx_thread_terminate(thread_ptr);
+            tx_byte_release(thread_ptr->tx_thread_stack_start);
+            tx_byte_release(thread_ptr);
+        }
+        return;
+    }
+
+    tx_thread_terminate(thread);
+    tx_byte_release(thread_ptr->tx_thread_stack_start);
+    tx_byte_release(thread);
+}
+
+usb_osal_sem_t usb_osal_sem_create(uint32_t initial_count)
+{
+    TX_SEMAPHORE *sem_ptr = TX_NULL;
+
+    tx_byte_allocate(&usb_byte_pool, (VOID **)&sem_ptr, sizeof(TX_SEMAPHORE), TX_NO_WAIT);
+
+    if (sem_ptr == TX_NULL) {
+        return NULL;
+    }
+
+    tx_semaphore_create(sem_ptr, "usbh_sem", initial_count);
+    return (usb_osal_sem_t)sem_ptr;
+}
+
+void usb_osal_sem_delete(usb_osal_sem_t sem)
+{
+    tx_semaphore_delete((TX_SEMAPHORE *)sem);
+    tx_byte_release(sem);
+}
+
+int usb_osal_sem_take(usb_osal_sem_t sem, uint32_t timeout)
+{
+    int ret = 0;
+
+    ret = tx_semaphore_get((TX_SEMAPHORE *)sem, timeout);
+    if (ret == TX_SUCCESS) {
+        ret = 0;
+    } else if ((ret == TX_WAIT_ABORTED) || (ret == TX_NO_INSTANCE)) {
+        ret = -USB_ERR_TIMEOUT;
+    } else {
+        ret = -USB_ERR_INVAL;
+    }
+
+    return (int)ret;
+}
+
+int usb_osal_sem_give(usb_osal_sem_t sem)
+{
+    return (int)tx_semaphore_put((TX_SEMAPHORE *)sem);
+}
+
+void usb_osal_sem_reset(usb_osal_sem_t sem)
+{
+}
+
+usb_osal_mutex_t usb_osal_mutex_create(void)
+{
+    TX_MUTEX *mutex_ptr = TX_NULL;
+
+    tx_byte_allocate(&usb_byte_pool, (VOID **)&mutex_ptr, sizeof(TX_MUTEX), TX_NO_WAIT);
+
+    if (mutex_ptr == TX_NULL) {
+        return NULL;
+    }
+
+    tx_mutex_create(mutex_ptr, "usbh_mutx", TX_INHERIT);
+    return (usb_osal_mutex_t)mutex_ptr;
+}
+
+void usb_osal_mutex_delete(usb_osal_mutex_t mutex)
+{
+    tx_mutex_delete((TX_MUTEX *)mutex);
+    tx_byte_release(mutex);
+}
+
+int usb_osal_mutex_take(usb_osal_mutex_t mutex)
+{
+    int ret = 0;
+
+    ret = tx_mutex_get((TX_MUTEX *)mutex, TX_WAIT_FOREVER);
+    if (ret == TX_SUCCESS) {
+        ret = 0;
+    } else if ((ret == TX_WAIT_ABORTED) || (ret == TX_NO_INSTANCE)) {
+        ret = -USB_ERR_TIMEOUT;
+    } else {
+        ret = -USB_ERR_INVAL;
+    }
+
+    return (int)ret;
+}
+
+int usb_osal_mutex_give(usb_osal_mutex_t mutex)
+{
+    return (int)(tx_mutex_put((TX_MUTEX *)mutex) == TX_SUCCESS) ? 0 : -USB_ERR_INVAL;
+}
+
+usb_osal_mq_t usb_osal_mq_create(uint32_t max_msgs)
+{
+    CHAR *pointer = TX_NULL;
+    TX_QUEUE *queue_ptr = TX_NULL;
+
+    tx_byte_allocate(&usb_byte_pool, (VOID **)&queue_ptr, sizeof(TX_QUEUE), TX_NO_WAIT);
+
+    if (queue_ptr == TX_NULL) {
+        return NULL;
+    }
+
+    tx_byte_allocate(&usb_byte_pool, (VOID **)&pointer, sizeof(uintptr_t) * max_msgs, TX_NO_WAIT);
+
+    if (pointer == TX_NULL) {
+        return NULL;
+    }
+
+    tx_queue_create(queue_ptr, "usbh_mq", sizeof(uintptr_t) / 4, pointer, sizeof(uintptr_t) * max_msgs);
+    return (usb_osal_mq_t)queue_ptr;
+}
+
+void usb_osal_mq_delete(usb_osal_mq_t mq)
+{
+    tx_queue_delete((TX_QUEUE *)mq);
+    tx_byte_release(((TX_QUEUE *)mq)->tx_queue_start);
+    tx_byte_release(mq);
+}
+
+int usb_osal_mq_send(usb_osal_mq_t mq, uintptr_t addr)
+{
+    return (tx_queue_send((TX_QUEUE *)mq, &addr, TX_NO_WAIT) == TX_SUCCESS) ? 0 : -USB_ERR_INVAL;
+}
+
+int usb_osal_mq_recv(usb_osal_mq_t mq, uintptr_t *addr, uint32_t timeout)
+{
+    int ret = 0;
+
+    ret = tx_queue_receive((TX_QUEUE *)mq, addr, timeout);
+    if (ret == TX_SUCCESS) {
+        ret = 0;
+    } else if (ret == TX_QUEUE_EMPTY) {
+        ret = -USB_ERR_TIMEOUT;
+    } else {
+        ret = -USB_ERR_INVAL;
+    }
+
+    return (int)ret;
+}
+
+struct usb_osal_timer *usb_osal_timer_create(const char *name, uint32_t timeout_ms, usb_timer_handler_t handler, void *argument, bool is_period)
+{
+    TX_TIMER *timer_ptr = TX_NULL;
+    struct usb_osal_timer *timer;
+
+    tx_byte_allocate(&usb_byte_pool, (VOID **)&timer, sizeof(struct usb_osal_timer), TX_NO_WAIT);
+
+    if (timer == TX_NULL) {
+        return NULL;
+    }
+    memset(timer, 0, sizeof(struct usb_osal_timer));
+
+    tx_byte_allocate(&usb_byte_pool, (VOID **)&timer_ptr, sizeof(TX_TIMER), TX_NO_WAIT);
+
+    if (timer_ptr == TX_NULL) {
+        return NULL;
+    }
+
+    timer->timer = timer_ptr;
+    timer->ticks = timeout_ms;
+    timer->is_period = is_period;
+    if (tx_timer_create(timer_ptr, (CHAR *)name, (void (*)(ULONG))handler, (uintptr_t)argument, 1, is_period ? 1 : 0,
+                        TX_NO_ACTIVATE) != TX_SUCCESS) {
+        return NULL;
+    }
+    return timer;
+}
+
+void usb_osal_timer_delete(struct usb_osal_timer *timer)
+{
+    tx_timer_deactivate((TX_TIMER *)timer->timer);
+    tx_timer_delete((TX_TIMER *)timer->timer);
+    tx_byte_release(timer->timer);
+    tx_byte_release(timer);
+}
+
+void usb_osal_timer_start(struct usb_osal_timer *timer)
+{
+    if (tx_timer_change((TX_TIMER *)timer->timer, timer->ticks, timer->is_period ? timer->ticks : 0) == TX_SUCCESS) {
+        /* Call the tx_timer_activate to activates the specified application
+             timer. The expiration routines of timers that expire at the same
+             time are executed in the order they were activated. */
+        if (tx_timer_activate((TX_TIMER *)timer->timer) == TX_SUCCESS) {
+            /* Return osOK for success */
+        } else {
+            /* Return osErrorResource in case of error */
+        }
+    } else {
+    }
+}
+
+void usb_osal_timer_stop(struct usb_osal_timer *timer)
+{
+    tx_timer_deactivate((TX_TIMER *)timer->timer);
+}
+
+size_t usb_osal_enter_critical_section(void)
+{
+    TX_INTERRUPT_SAVE_AREA
+
+    TX_DISABLE
+
+    return interrupt_save;
+}
+
+void usb_osal_leave_critical_section(size_t flag)
+{
+    int interrupt_save;
+
+    interrupt_save = flag;
+    TX_RESTORE
+}
+
+void usb_osal_msleep(uint32_t delay)
+{
+#if TX_TIMER_TICKS_PER_SECOND != 1000
+#error "TX_TIMER_TICKS_PER_SECOND must be 1000"
+#endif
+    tx_thread_sleep(delay);
+}
+
+void *usb_osal_malloc(size_t size)
+{
+    CHAR *pointer = TX_NULL;
+
+    tx_byte_allocate(&usb_byte_pool, (VOID **)&pointer, size, TX_WAIT_FOREVER);
+
+    return pointer;
+}
+
+void usb_osal_free(void *ptr)
+{
+    tx_byte_release(ptr);
+}
\ No newline at end of file