Objective To study the effect of medical clowns on crying and pain of children under perianaesthesia. Methods From January 2017 to December 2017, 285 children with perianaesthesia underwent hernia elective surgery in the pediatric surgery department of our hospital were selected as subjects for the study. They were divided into 143 children in the intervention group and 142 children in the control group by random number method. Results The crying time of the children in the intervention group decreased significantly before and after surgery (P＜0.05). The pain of the children in the intervention group was significantly lower than that of the control group (P＜0.05) at the three nodes of vein puncture, anesthesia resuscitation and 6h postoperative. The dosage of postoperative analgesic agents and the mean hospitalization days of the children in the intervention group were better than those in the control group (P＜0.05). Conclusion The intervention of clowns in the perianaesthesia period can effectively reduce the pain of children, shorten the crying and hospitalization time, and save the cost of hospitalization, which is of positive significance for clinical promotion.