Major depressive disorder (MDD) is a major global health challenge and postnatal women may be at an increased risk for this disorder. Very few studies have tested this hypothesis in sub-Saharan Africa (SSA), so it is uncertain whether risk factors implicated elsewhere in the world are relevant in SSA. We explored prevalence and risk factors for MDD and depressive symptomatology among postnatal mothers in Kampala. Three hundred postnatal mothers at Nsambya Hospital were assessed for MDD using the DSM IV-based MINI; prevalence and risk factors were determined using frequencies and regressions, respectively. Four women (1.33%) had MDD; however, 94 (31%) had ‘sub-threshold’ or depressive symptomatology, with which partner violence is particularly associated. MDD is rare among postnatal women in a paying hospital in Kampala; however, the high prevalence of depressive symptomatology suggests susceptibility to MDD. Longitudinal studies should investigate this hypothesis and the susceptibility due to partner violence should guide appropriate interventions.