The effectiveness of a brief intervention based on individual cognitive behavioral counseling in mothers with signs of postnatal depression was evaluated. Patients undergoing a complicated delivery were invited to participate. Women who scored above a cut-off level (>12) on Edinburgh Postnatal Depression Scale (EPDS) were randomized to either a brief individual cognitive behavioral counseling comprising three weekly 1 hour sessions (n = 33) or standard care (n = 34). Measures of postnatal depression were collected from EPDS, 1 month after birth and 1 month after treatment. Both groups showed a significant decline from baseline to follow-up, mean scores declined from 16.9 to 7.6 (intervention group) vs. 13.6 to 9.9 (control group; p < 0.001). There was a significant interaction effect (Group*Time) between the intervention and the control group showing a more rapid decline of EPDS scores for the intervention group (p < 0.001). The results suggest that brief cognitive behavioral counseling is an effective treatment in women at risk for developing postnatal depression.