Significant health disparities in the U.S. place low-income and racial and ethnic minority families at greater risk for parental depression, stress and poorer outcomes for children. The goal of this quasi-experimental pilot study was to assess the initial feasibility, acceptability, and efficacy of an intervention aimed at reducing stress and depression in a sample of low-income expectant parents early in pregnancy. Twenty-four couples (48 participants) were assigned to the 6-week PREParing for Parenthood (PREP) intervention and 22 couples (46 participants) were assigned to a treatment-as-usual comparison group. The group intervention consisted of six sessions during pregnancy and was taught by paraprofessionals in a community setting. The psychoeducational group was partner-inclusive and focused on a) depression reduction and stress management and b) enhancing the co-parent relationship. Interviews were completed at baseline and post-intervention to assess for depression (CES-D), perceived stress (PSS), and physiological stress via hair CORT. Analyses indicated significant program effects for mothers’ depression and fathers’ perceived stress. No significant effects were observed for mothers’ perceived stress, fathers’ depression, or physiological stress. The brief and accessible nature of the PREP program makes it a promising candidate to enhance at-risk parents’ mental health during a critical window of pregnancy.