Purpose: To test the effectiveness of a cognitive-behavioral group intervention in reducing depressive symptoms, negative thinking, and chronic stressors in low-income, single mothers at risk for depression. Design and Methods: A randomized, controlled prevention trial was conducted with 136 low-income, single mothers with children between the ages of 2 and 6 years. Each participant was screened before enrollment and was determined to be at risk for depression. Participants were randomly assigned to either the control or experimental group. The experimental group was invited to participate in a 4- to 6-week cognitive-bebavioral group intervention. Data on depressive symptoms, negative thinking, and chronic stressors were collected via self-report questionnaires from control and experimental groups at baseline, 1 month, and 6 months after the intervention to assess the effects of the intervention. Findings: Compared with those in the control group, women who received the intervention had a greater decrease in depressive symptoms, negative thinking, and chronic stressors; these beneficial effects were maintained over a 6-month period. Conclusions: The findings indicate the effectiveness of this cognitive-behavioral group intervention and show the beneficial effects of reducing negative thinking via the use of affirmations and thought-stopping techniques.