Background: Adolescent pregnancy is an ongoing public health and public policy concern in the United States. While the rates have steadily declined, current data may suggest that rates are once again increasing. In the United States, Hispanics currently have the highest teen birth rate, or 83 births per 1,000 teens, more than double the national rate. This teen birth rate has also been the most resistant to decline when compared to women of other racial ethnic groups. The most essential source of support is the adolescent's partner yet few studies have detailed the roles of male partners in adolescent mothers' lives. This study addresses the issues concerning paternal involvement and the effects on an adolescent mother's parenting. Methods: The effects of paternal involvement on the quality of maternal parenting were studied in 77 Mexican American adolescent mothers. Multiple linear regression analyses were conducted at 2 different time points; 6 months postpartum and 12 months postpartum to assess whether adolescent mothers who perceive the father of the baby's involvement as high demonstrate higher quality of parenting that adolescent mothers who perceive low involvement of the baby's father. Additionally at 12 months postpartum, to test an across-time effect, such that high father involvement at 6 months postpartum is associated with adolescent mothers' parenting at 12 months postpartum, a regression analysis was conducted incorporating the level of father involvement at 6 months postpartum. Results: At 6 months postpartum, there was a significant relationship between the predictor, paternal involvement, and quality of maternal parenting, adjusting for all other variables (p= 0.033), however the main effect of paternal involvement is difficult to discern due to the significant interaction between paternal involvement and parenting stress (p= 0.036). At 6 months postpartum, results indicate that the level of quality of maternal parenting varies with level of parenting stress and level of paternal involvement. At 12 months postpartum the main predictor, was not be significantly associated with maternal parenting (p= 0.067). However, parenting stress and harsh parenting behaviors were significantly associated with quality of maternal parenting (p= 0.010 and p < 0.001, respectively). In the final regression model, at 12 months postpartum, paternal involvement at 12 months postpartum, parenting stress, and harsh parenting behaviors were all significantly associated with quality of maternal parenting (p= 0.015, p= 0.003, and p= 0.001). In addition, the level of paternal involvement at 6 months postpartum was significantly, but negatively, associated with quality of maternal parenting (p= 0.029).