Patients with ovarian clear cell adenocarcinoma (OCCA) show a poor response to conventional platinum-based chemotherapy. Recently, it was reported that combination chemotherapy with cisplatin plus irinotecan hydrochloride (P-CPT) achieves high response rates for primary advanced and recurrent or resistant OCCA. We retrospectively reviewed the outcome of 20 OCCA patients treated with P-CPT by the Gynecology Service at The Jikei University Hospital after initial surgery. These patients received a total of 101 cycles of P-CPT, with a median of 5 cycles each. Two complete responses (CRs) were obtained in the three patients with measurable disease, and response duration was 7 and 15 months, respectively. One patient had stable disease (SD), and the time to progression was 5 months. The estimated 3- and 5-year survival rates were 69% and 69%, respectively. Our current data and previous reports suggest that P-CPT is a candidate first-line chemotherapy regimen for OCCA.