Objective To investigate the surgical treatments of Morel-Lavallée lesion with perineal lacerations. Methods From March 2003 to June 2009, 18 cases of Morel-Lavallée lesion with perineal lacerations were treated. There were 16 males and 2 females with a median age of 28.5 years (range, 3-54 years). The time between the injury and hospital ization ranged from 3 hours to 7 days. The lesions were in the greater trochanter (2 cases), the gluteal (2 cases), the lumbar flank (1 case), the lumbar sacrum (3 cases), the pelvic girdle (7 cases), and the hip (3 cases). All the cases were compl icated with perineal lacerations, which included male genital ia defect (2 cases), mangled genital ia (2 cases), and genital ia injuries with anal injuries (14 cases). The main treatments included repeated debridement, external fixation of fractures, vacuum seal ing drainage, skin grafting, reconstruction of genital ia, and anoplasty. Results Three cases died after operation. Two cases died of multiple system organ failure, 1 case died of septic shock. Three cases were amputated and the causes were mangled extremities (2 cases) and osteofascial compartment syndrome (1 case). In 15 survivors, the average time of operations was 3.6 times (range, 3-8 times) and the average hospital ization days was 43.3 days (range, 32-108 days). After a follow-up of 6 months to 2 years, all perineal wounds healed. Anals recovered the normal defecation while one with ostomy was waiting for the secondly resetting of the bowels. Conclusion The treatments of Morel-Lavallée lesion with perineal lacerations were significantly different from simple close Morel-Lavallée lesion. With high mortal ity and disabil ity, Morel-Lavallée lesion with perineal lacerations require more challenging treatment protocols among which the most important is the soft tissue management and nutrition. The satisfactory outcomes come from joint efforts of multiple departments.