Objective: To measure sexual activity in a clinic population of partnered female cancer survivors, and to better understand reasons for sexual inactivity in this population. Materials and methods: Partnered peri- or post-menopausal cancer survivors seen at a specialty clinic for menopause symptoms after cancer completed Fallowfield's Sexual Activity Questionnaire, quality of life measures (the Functional Assessment of Cancer Therapy General, Breast Cancer, and Endocrine Symptom Scales), and the Greene Climacteric Scale. Responses were compared between those who were sexually active and those who were not. Results: Of 316 partnered women who reported sexual activity status, most were breast cancer survivors (n = 268, 85%) and were sexually active (n = 227, 72%). Women who were not sexually active (n = 89, 28%) were slightly older than those who were active (53.1. v 51.0 years, p = 0.049) but did not differ in menopausal status, time since cancer diagnosis, or treatment with chemotherapy, anti-estrogenic endocrine therapy or menopausal hormone therapy. Loss of interest in sex (78%) and being too tired (44%) were the most common reasons for sexual inactivity. Those who were not sexually active were more likely to be dissatisfied with their sex lives (adjusted odds ratio (aOR) 3.52, 95% CI 1.66-7.48) and to have lost interest in sex (aOR 2.12, 95% CI 1.22-3.67). Compared with sexually active women, sexually inactive women were significantly less likely to feel sexually attractive or "able to feel like a woman" (respectively, aOR 2.51, 95% CI 1.01-6.24; aOR 2.21, 95% CI 1.32-3.71) and more likely to feel bothered by a weight change and self-conscious about the way they dressed, and to be bothered by hair loss (respectively, aOR 1.84, 95% CI 1.10-3.05; aOR 2.75, 95% CI 1.63-4.64; aOR 1.85, 95% CI 1.04-3.29). Those who were not sexually active had significantly lower average scores on breast-cancer-related quality of life than sexually active women but did not differ in physical, social or functional well-being or menopause-related quality of life. Pain with intercourse and vaginal dryness were equally common in both groups (respectively, sexually inactive 45.5% v. active 38.3%, aOR 1.28, 95%CI 0.75-2.18; 48.8% v. 49.5%, aOR 0.94, 95% CI 0.57-1.56). Conclusions: Over one-quarter of partnered cancer survivors in this clinic-based sample were not sexually active. Sexually inactive women were more dissatisfied with their sex lives, felt less attractive and more self-conscious about their appearance. The reasons for sexual inactivity in cancer survivors are multifaceted and complex and rates of vaginal dryness and dyspareunia did not differ between sexually active and inactive women, suggesting that interventions to improve sexual function which are limited to treating vaginal dryness are unlikely to be effective.