This study was conducted to determine prevalence and risk factors for retrovirus infection of infected cats in a large cat population in Germany by evaluation of 17,462 client-owned cats that were tested for the presence of feline immunodeficiency virus (FIV) antibodies or feline leukaemia virus (FeLV) antigen. The owners of a subset of 100 cats were contacted to determine their cat's survival times. Prevalence of FIV and FeLV was 3.2% and 3.6%, respectively, remaining stable for FIV, but decreasing for FeLV (6-1%) over 10 years. Median age was 6 years in FIV- and 3 years in FeLV-infected cats. Risk factors for FIV infection were male gender, older age, mixed breed, access to outdoor, aggressive behaviour, and FeLV co-infection; and for FeLV infection contact to other cats, aggressive behaviour, and FIV co-infection. Median survival time of FIV-infected cats was not significantly different to non-infected cats, whereas FeLV-infected cats had significantly shorter median survival times than non-infected cats.