Postpartum depression and postpartum stress are often mentioned in women who have given birth. However, the transition to parenthood also has an impact on men’s mental health which can also cause postpartum depression and postpartum stress. The importance of mental health is significant for both parents, because it all affects the relationship in which they find themselves and the child's life. Men are at increased risk of mental health problems during the transition to fatherhood ,as well as during the postpartum period. It has been shown that the mental health of fathers during the postpartum period affects their work, and that they have a guilty conscience because they spend too little time with the child in the first year of the child's life. The aim of this study was to examine men, who became fathers within a year, how parenting affects their lives, whether men think they can develop postpartum depression and how stressed they are after becoming fathers. The study involved 252 men, who became fathers within a year. Differences in categorical variables were tested by Hi-square test and, when necessary, by Fisher's exact test. According to the results, men are under great stress during the first year of a child's life, and have a guilty conscience that they do not participate enough in child care. There was a higher level of stress during their partners' pregnancy than during the act of birth itself. There were also recorded higher levels of stress in men in whom the partner felt postpartum blues after childbirth than in those in whom the partner felt well. The obtained results show that men consider it of great importance to educate future parents about parenting.