Objective: The quality-of-life concept has increasingly gained attention, but an important aspect has been neglected, which is the sexual function of patients with kidney cancer after surgery. The aim of this study was to explore the impact of nephrectomy on sexual function in patients with kidney cancer and the information patients received with this regard. Material and methods: We conducted a retrospective study of patients who underwent nephrectomy or nephro-ureterectomy within a 5-year period at the Department of Urology, Odense University Hospital, Denmark. Among 310 patients having undergone surgery, 226 were still alive and eligible for participation. Their records were reviewed, and a validated questionnaire concerning their sex life was mailed to them. All participants were invited to take part in a semi-structured interview in person or by phone. Results: Of 154 former patients who replied, 95 were men (mean age, 66 years, range 37–89), 59 were women (mean age 63 years, range 26–87). A significant difference was observed regarding problems with sexual relationships prior to operation compared after (P<0.0001). Seven patients (5%) had been informed about potential effects and changes in their sex life following operation. Both male and female participants were worried about their sex life (61.4%). Among sexually active male responders, 54.7% reported having some degree of erectile dysfunction. Conclusion: Patients experience significantly more problems in their sexual relationships after surgery. Very few were informed about this, showing the need to offer sex counselling before surgery. More research is required to fully comprehend the magnitude of the problem.