Objective: The aim of this study was to test the efficacy of technology-based weight loss interventions for endometrial cancer (EC) survivors with obesity. Methods: EC survivors with obesity (n = 196) from three medical centers completed assessments for knowledge of obesity as a risk for EC and interest in weight management. Forty-one women were randomized to a 6-month intervention: telemedicine with Wi-Fi scales, text messaging (texting), or enhanced usual care (EUC). Changes in anthropometrics and psychosocial measures were analyzed. Results: One-third of survey participants lacked awareness that obesity increased the risk of EC, and 40% misclassified their body mass. There were no significant differences in weight loss across interventions (mean = −4.4 kg, SD = 6.5 kg). Telemedicine showed improvements in physical health and cancer-related body image (Ps = 0.04) compared to texting and in sexual functioning compared to EUC (P = 0.03). Total physical activity was increased in EUC compared with telemedicine (P = 0.01), and vigorous physical activity was increased in EUC compared with both interventions (P = 0.01-0.03); walking significantly increased in texting compared with telemedicine (P = 0.02). Conclusions: Technology-based lifestyle interventions in EC survivors with obesity were accessible and resulted in weight loss and improved quality of life. EUC also produced weight loss, demonstrating a potential for beginning weight management with information on specific diet and exercise goals.