Background: Mucinous urachal neoplasms presenting with pseudomyxoma peritonei are rare pathologies, which usually manifest with abdominal pain, mucosuria, and imaging findings of an infraumbilical midline mass and bladder dome. Cytoreduction complemented with hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment strategy associated with better survival rates, disease-free time, and better quality of life compared with systemic chemotherapy. Case Description: We describe an unusual case of a patient with peritoneal pseudomyxoma secondary to mucinous adenocarcinoma of the urachus, who underwent complete macroscopic cytoreduction and intraoperative HIPEC with an adequate response to HIPEC, without imaging or clinical evidence of relapse at 24 months of follow-up. Conclusion: Cytoreductive surgery associated with HIPEC can be considered a treatment strategy for mucinous urachal neoplasms presenting with peritoneal pseudomyxoma.