The prevalence of HIV has been continually increasing both in urban and rural Ethiopia. As yet, there has been no report on the magnitude of the problem in the elderly and rural population. This study assessed the seroprevalence of HIV and syphilis infection among 706 elderly and predominantly rural subjects in Northwest Ethiopia. Socio-demographic information was collected using a structured questionnaire. Venous blood was collected and the serostatus of HIV and that of syphilis were checked by ELISA and RPR, respectively. The total HIV-1 seroprevalence was 5% (35/706). Sex-specific prevalences of HIV for males and females were 5.6 and 4.7% respectively. A 4.2% difference in prevalence was observed by area of residence, which was statistically significant, P = 0.018. Only 6% of subjects positive for syphilis were also positive for HIV, while 4.9% of subjects negative for syphilis were positive for HIV. The data indicates that the prevalence of HIV among elderly people in Northwest Ethiopia was high. This indicates the importance of involving the elderly in HIV/AIDS prevention and control programs.