BACKGROUND. Few studies have evaluated lymphedema after gynecological cancer treatment. The aim of this research was to establish prevalence, correlates, and supportive care needs of gynecological cancer survivors who develop lymphedema. METHODS. in 2004, a population-based cross-sectional mail survey (56% response rate) was completed by 802 gynecological cancer survivors. The questionnaire included demographic questions, a validated, generic supportive care needs measure, and a supplementary, newly developed, lymphedema needs module. RESULTS. Ten percent (95% confidence interval [Cl], 8%-12%) of participants reported being diagnosed with lymphedema, and a further 15% (95% Cl, 13%-17%) reported undiagnosed "symptomatic" lower limb swelling. Diagnosed lymphedema was more prevalent (36%) amongst vulvar cancer survivors. For cervical cancer survivors, those who had radiotherapy or who had lymph nodes removed had higher odds of developing swelling. For uterine and ovarian cancer survivors, those who had lymph nodes removed or who were overweight or obese had higher odds of developing swelling. Gynecological cancer survivors with lymphedema had higher supportive care needs in the information and symptom management domains compared with those who had no swelling. CONCLUSIONS. This population-based study provided evidence that lymphedema is a morbidity experienced by a significant proportion of gynecological cancer survivors and that there are considerable levels of associated unmet needs. Women at risk of lymphedema would benefit from instructions about early signs and symptoms and provision of referral information.