OBJECTIVE To investigate the predictive factors for the response to platinum/paclitaxel based first-line adjuvant chemotherapy in advanced ovarian cancer. METHODS Forty-two patients with advanced ovarian cancer underwent complete resection plus platinum/paclitaxel as first-line adjuvant chemotherapy. The clinical outcomes were observed. Immunohistochemistry was used to detect the expression of p53, a tumor suppressor protein, and P-glycoprotein (Pgp), a multi-drug resistance associated gene product, in the specimens resected from operation. Retrospectively analysis of 42 cases r patients with. To calculate the complete response (CR) rate and early recurrence (ER) rate and to observe. The relationship between the parameters about clinical outcomes and some clinico-pathological variables, such as age, pathological type, differentiation degree, residual tumor, and molecular markers p53 and Pgp, was analyzed. RESULTS Twenty-four patients (57%) showed CR and 7 (13%) showed ER. The CR rate of the p53 positive patients was 74%, higher than that of the p53 negative patients (44%, P = 0.065). The ER rate of the patients with residual tumor less than 2 cm was 4%, significantly lower than those with residual tumor > or = 2 cm (P = 0.018). Logistic regression analysis indicated that Pgp positivity and residual tumor > or = 2 cm were independent risk factors of ER. CONCLUSIONS Residual tumor, p53, and Pgp expression are predictive factors for the response to platinum/paclitaxel first-line adjuvant chemotherapy in advanced ovarian cancer. The p53 positive patients are more sensitive to this protocol, and the Pgp positive patients and the patients with residual tumor > or = 2 cm are more resistant to this protocol.