The possible reasons for ankle joint soreness while sleeping include soft tissue injury, osteoporosis, arthritis, etc. 1. Soft tissue injury: If you are tired and over-exercise during the day, it is very likely that the peri-foot tissue or plantar tissue will be subjected to excessive local stress, which will lead to local soft tissue injury, so the ankle joints will be sore at night, which can be relieved by hot compresses and other ways. 2. Osteoporosis: it is often caused by a long time of calcium deficiency, and it occurs in middle-aged and old people. When sleeping at night, the ankle may be sore, accompanied by fatigue, numbness and so on. 3. Arthritis: rheumatoid arthritis, rheumatoid arthritis, degenerative osteoarthritis and so on. The onset of the disease can cause pain in the joints and restriction of activities. There can also be a feeling of soreness in the ankle joints while sleeping. It is recommended to go to the hospital in time to clarify the cause of the disease and standardize the treatment if your ankle is sore when you sleep.