Objective:To evaluate the effects of two types of superficial musculoaponeurotic system(SMAS) reservations on the prevention of Frey’s syndrome and tumor recurrence after parotidectomy.Methods:125 patients suffering from benign tumors of parotid gland were divided randomly into three groups(Ⅰ～Ⅲ groups):groupⅠ:Parotidectomy with free SMAS reservation in 39 cases;groupsⅡ:Parotidectomy with non-free SMAS reservation in 46 cases;groups Ⅲ:Parotidectomy without SMAS reservation in 40 cases.After operation 6 to 12 months

all the 125 patients were evaluated for gustatory sweating by both questionnaire and minor starch-iodine test.All the patients were followed up for tumor recurrence after operation 2 to 3 years.Results:Subjective evaluation of Frey’s syndrome revealed that the incidence rates of Ⅰgroup

Ⅱgroup and Ⅲ group were 5.1%(2/39)

26.1%(12/46) and 55.0%(22/40) respectively(P<0.05).Objective evaluation of Frey’s syndrome revealed that the incidence rates of Ⅰgroup

Ⅱgroup and Ⅲ group were 10.3%(4/39)

37.0%(17/46) and 72.5%(29/40) respectively(P<0.05).There was not tumor recurrence case in all 125 patients.Conclusion:Reservation of SMAS is an effective method for prevention of Frey’s syndrome after parotidectomy.The incidence rate of free SMAS reservation is lower than that of non-free SMAS reservation.Reservation of SMAS does not increase recurrence rate of benign parotid tumor.