Testicular cancer is the most frequent malignancy in men between 20 and 40 years of age. This is a period in life in which important life events take place, such as starting a career and establishing a relationship. The goal of the study was to explore self-esteem, social support, and mental health in 3 groups of survivors of testicular cancer: singles, those with the same partner as at diagnosis (relationship during testicular cancer), and those with a partner they met after completion of treatment (relationship after testicular cancer). A total of 129 survivors completed the Social Support List, the Rosenberg self-esteem scale, and the subscale mental health of the RAND-36. Mean time since diagnosis for single survivors was 8.3 years (range 1-23), for survivors with a relationship during testicular cancer 9.3 years (range 1-24), and for survivors with a relationship after testicular cancer 13.6 years (range 1-24). Levels of social support were equal in groups, but satisfaction with support was not. Survivors with a relationship during testicular cancer were most satisfied with support, and had the highest self-esteem and mental health. Survivors with a relationship after testicular cancer reported the next best levels of functioning but had the same mental health as singles. Singles and survivors with a relationship established after testicular cancer had a lower mental health than a reference group of men. The difference in self-esteem between singles and survivors of testicular cancer with a relationship during testicular cancer appeared most distinct and was clinically relevant. Mental health was predicted by different factors for the 3 groups. Being single at diagnosis seems to cause a vulnerability that remains when survivors do develop a relationship after treatment is completed because these groups are at risk for a lower mental health.