Inhibition of STAT3 activity with a JAK inhibitor (JAKi) significantly enhanced the efficacy of gefitinib against human ovarian cancer cells both in vitro and in vivo. Our findings indicate that combined treatment with the EGFR inhibitor, gefitinib, and a JAK/STAT3 pathway inhibitor could potentially improve ovarian cancer treatment success. This evidence concerns the gene STAT3 and ovarian cancer.