A cross-sectional survey was conducted on 10,468 rural and semi-urban adults in an Ethiopian district using the Self Reporting Questionnaire (SRQ) to detect the prevalence of mental distress and its association with socio-demographic risk factors. Fifty-eight per cent of the study population were women, 74% were Muslim, 79% were illiterate. Those experiencing 11 or more symptoms out of the 20 SRQ items were considered as having mental distress. Accordingly, the prevalence of mental distress was 17%, which is comparable with the previous hospital-based studies in Ethiopia and elsewhere. However, it was higher than the previous community-based studies in Ethiopia. Mental distress was more prevalent among women. Part of the explanation was that women in the study population were older and that they were more often widowed or divorced, which were factors associated with mental distress. Illiteracy, which was more common among women and older individuals, was also independently associated with mental distress.