We report a 40 years old female that presented whith an ovarian tumor and ascites. The exploratory laparotomy revealed a mucocele of the appendix that was informed as a cystadenoma of the appendix in the fast biopsy. The definitive pathological diagnosis, a cystadenocarcinoma of the appendix, motivated a second intervention preforming a right hemicolectomy, left adnexectomy and omentumectomy. Three years later she presented with an abdominal mass and was subjected to a fetal hysterectomy and right adnexectomy. The pathological diagnosis was a mucinous cystadenocarcinoma with peritoneal involvement. The patient completed five years of follow up since the first intervention and is free of tumor Pseudomixome peritoneai generally is a. tumor of ovarian origin, followed by the appendix. Surgical treatment must include the excision bf neighboring compromised organs. The follow up must be lengthy considering the possibility of late recurrences