There may be several reasons for knee pain in the middle of the night: 1, calcium deficiency, if the body long-term calcium deficiency, may lead to knee pain, but also accompanied by foot cramps, lower limb muscle pain, muscle weakness and other symptoms, long-term calcium deficiency may also lead to osteoporosis, poor sleep quality, treatment can be calcium carbonate D3 calcium, vitamin D to promote calcium ion absorption. 2, arthritis, if the knee joint long-term overwork or weight bearing, may lead to knee muscle strain, resulting in bacterial inflammation. It may lead to strain on the knee muscles and produce aseptic inflammation, resulting in sore knees. The treatment can be given topical compound wind chasing cream to relieve soreness, hot towel compresses, Chinese herbal compresses, Chinese herbal fumigation and other physical therapy to relieve symptoms. 3, rheumatic diseases, if suffering from rheumatic diseases, such as rheumatoid arthritis, gout, etc., in the cold or strain may induce disease, patients need to go to the hospital to clarify the cause of symptomatic treatment.