Management of advanced-stage uterine serous carcinoma (USC) is uncertain, and postsurgical therapeutic options swing between radiation and chemotherapy. The aim of this study is to evaluate the utility of radiotherapy compared to platinum-based chemotherapy in women with advanced-stage USC. We retrospectively identified cases of USC at our institution. Survival distributions were calculated by the Kaplan-Meier method. Two-tailed t-tests were used to compare time to progression and time to death. We identified 24 women diagnosed with either stage III or IV USC. Time to progression for women receiving radiotherapy was 5.3 months as compared with 12.4 months for women receiving chemotherapy (P = 0.01). Mean time to death for the radiotherapy group was 8 months compared to 18 months in the chemotherapy group (P = 0.04). Kaplan-Meier survival curves were significantly different between the two groups (P = 0.01). While radiotherapy appears to control USC recurrences in the pelvis, the disease often recurs distantly. When compared to radiotherapy, platinum-based chemotherapy appears to increase disease-free survival and time to death in women with advanced-stage USC.