Leg cramps at night in the elderly are a common phenomenon, mainly due to abnormal calcium metabolism, commonly caused by calcium deficiency. Elderly patients often have low dietary and digestive absorption functions, which can lead to insufficient calcium absorption, and osteoporosis can also occur. If blood calcium is significantly low, it can lead to increased neuromuscular excitability, and when resting at night, the autonomic function is reduced, and lighter stimulation can lead to the occurrence of leg cramps. Timely examination at the hospital to clarify the calcium metabolism and timely administration of medication can reduce the occurrence of cramps. In addition to medication, proper attention to warmth during treatment and avoiding cold and strain can significantly improve the treatment effect. At the same time, lower limb artery occlusion can also lead to leg cramps. If calcium supplementation has no effect, it is necessary to check the lower limb artery ultrasound for clear diagnosis and treatment.