Appendiceal mucinous adenocarcinoma accompanied by cysts ruptures by surgical operation and leakage of mucus into the peritoneal cavity results in deterioration of prognosis.We report a case where the appendix mucinous adenocarcinoma was safely excised by laparoscopically preceding vascular treatment, lymph node dissection and intestinal dissection.The case was a woman in her forty-age suffering from the right lower quadrant and fever; no improvement was observed even when antibiotics were administered.A cystic lesion with a maximum diameter of 75mm was found on the right side of the pelvis with CT, and numerous lymph adenopathy was observed along the iliac artery.Preoperative diagnosis was diagnosed as appendiceal mucinous adenocarcinoma suspected and laparoscopic resection of the cecum was performed with the above procedure without breaking the cyst.Pathological diagnosis was findings of appendicular mucinous adenocarcinoma.She was discharged on the 7th postoperative day after surgery, 6 months after surgery without relapse survival.In order to resect a cystic tumor by laparoscopic surgery, it is considered to be useful to take care to prevent the forceps from touching the tumor, and perform a procedure that precedes vascular dissection and intestinal dissection.