We examined whether sociodemographic, physical, reproductive, psychological and clinical factors at the time of diagnosis were related to women's sexual well-being 3-5 years following treatment for endometrial cancer.Of the 1,399 women in the Australian National Endometrial Cancer Study, 644 completed a follow-up questionnaire 3-5 years after diagnosis. Of these, 395 women completed the Sexual-Function Vaginal Changes Questionnaire, which was used to assess sexual well-being. Based on two questions assessing worry and satisfaction with their sexuality, women were classified into lower and higher sexual well-being. Multivariable-adjusted logistic regression models were used to examine sexual well-being 3-5 years following cancer treatment and the factors associated with this at diagnosis and at follow-up.Of the 395 women, 46 % (n = 181) were categorized into the "higher" sexual well-being group. Women who were older (odds ratio [OR] = 1.97; 95 % confidence limit [CI], 1.23-3.17), high school educated (OR = 1.75; 95 % CI, 1.12-2.73), who reported good mental health at the time of diagnosis (OR = 2.29; 95 % CI, 1.32-3.95) and whose cancer was treated with surgery alone (OR = 1.93; 95 % CI, 1.22-3.07) were most likely to report positive sexual well-being. At 3-5 years post-diagnosis, women with few symptoms of anxiety (OR = 2.28; 95 % CI, 1.21-4.29) were also most likely to report positive sexual well-being.Psychological, sociodemographic and treatment factors are important to positive sexual well-being post-cancer. Care that focuses on maintaining physical and psychosocial aspects of women's lives will be more effective in promoting positive sexual well-being than care that focuses solely on physical function.