Pelvic floor relaxation syndrome is a group of syndromes in which the transverse pelvic floor muscles do not relax or even contract paradoxically during defecation, resulting in difficulty in defecation. The cause is still unknown, but it is generally believed that the syndrome is related to spastic hypertrophy of the puborectalis muscle, so it is also called “puborectalis syndrome”. Physiologically speaking, during normal defecation, the external sphincter of the puborectal muscle relaxes, relaxing the anal canal and enlarging the rectal angle of the anal canal so that feces can be discharged smoothly. The main clinical manifestation of pelvic floor dyslaxation syndrome should be difficulty in passing stool, even if it is formed soft stool, the patient will have a feeling of fullness and distension in the perineum, and the anus cannot be opened. The diagnosis of this disease is mainly based on electromyography and fecal imaging. Electromyography shows synchronous paradoxical discharge of multiple muscle groups in the pelvic floor. Fecal imaging shows that the anorectal angle does not become larger or even smaller during forceful defecation. There is no good treatment for pelvic floor dyslaxation syndrome, but the main treatment is conservative, such as increasing the amount of crude fiber in the diet and drinking more water. Laxatives can be used, but do not rely on them. It is best to alternate between oral laxatives and topical cathartics (20-40 ml each time) and saline enemas (500 ml each time). For those who are ineffective in long-term conservative treatment and have significant muscle hypertrophy and a significantly lengthened anal canal, partial resection of the posterior puborectalis muscle can be performed to treat the problem, with good results in some patients.