Background: With the prevalence of assisted reproductive technology (ART), the incidence of ectopic pregnancy (EP) is increasing, especially in patients with salpingectomy or proximal tubal occlusion. Methods: A total of 11,609 women who were undergoing ART and had undergone salpingectomy or proximal tubal occlusion, and 5388 women who achieved a clinical pregnancy were included in the study. Statistical analysis was used to determine whether the number of embryos transferred was associated with EP. Results: Both the number of embryos transferred and the day of embryo transfer differed significantly between those with and without EP (p 0.05), while the number of embryos transferred was associated with interstitial pregnancy (IP) (p 0.05) in those undergoing frozen-thawed embryo transfer (ET) cycles. Following multivariate modeling, the odds of having an EP in women undergoing frozen-thawed ET cycles increased with the number of embryos transferred (odds ratio [OR] 2.003, 95% confidence interval [95% CI] 1.036–3.876). Conclusions: The embryo transfer number was considered a risk factor for EP in patients undergoing frozen-thawed ET who had undergone salpingectomy or proximal tubal occlusion.