Postpartum pain in the buttocks is often a normal phenomenon, the specific reasons are as follows: 1, chronic fasciitis: because in late pregnancy, due to the gradual increase of the fetus, the uterus gradually rise, the weight of the whole body will be tilted backwards, the back, buttocks will become the load point of strength, so often subject to local compression, there will be chronic fasciitis in the buttocks, so manifested as soreness and discomfort in the buttocks. 2, pelvic injury. It may be that the fetus is larger during delivery, and when the fetus comes out of the pelvis, it causes the separation of the pubic symphysis, so that there will be pelvic injury, mainly manifesting as pain, soreness and discomfort at the pubic symphysis, like this case can generally be used after delivery to put pressure around both sides of the pelvis with a pelvic belt or waist girth, so as to reset the pubic symphysis, which can also reduce some symptoms in the pelvic area and hip area.