Objective To determine the incidence of respiratory disfunction after general aneasthesia in postanesthesia care unit（PACU） and access its relationship with residual paralysis. Method 623 adult patients, scheduled for elective surgical procedures, were enrolled in the study. On arrival to the PACU, the train-of-four ratio was assessed using electromyography. Extubation was determined using standard clinical criteria. Patients were divided into three groups according to the TOF measured after extubation, group A(TOF> 0.9); group B(TOF 0.7-0.9); group C(TOF <0.7). The number of patients who have respiratory disfunction were recorded in each group. Results The incidence of respiratory disfunction after general aneasthesia in PACU is 4.5%. There were 7(1.6%), 9(8.0%), and 12(30.8%) patients who had respiratory disfunction in group A, B, C respectively. The most common complications are hypoxemia and airway obstruction. The incidence of respiratory insufficiency in group C is significant higher than that of groups A and B,and it is significant higher in the group B than in the group A. Conclusion Patients with residual paralysis(TOF <0.9) are more likely to have postoperative respiratory disfunction and should be given neuromuscular monitoring perioperatively. The timing of extubation is very important.