As a reflection of the culture and norms of the school community, the school climate (SC) is a potential factor connected to students’ major behavior problems (BP). Parental involvement (PI) is considered as an essential factor for SC, contributing to promote good students’ educational results, as well as better social functioning. The present study aimed to analyze the mediating effect of PI on the relationship between SC and BP, taking into consideration the school personnel perceptions. A total of 329 school personnel (teachers versus no teachers) aged between 29 and 66 (M = 50.78, SD = 7.56), mainly female (79%), were integrated in the sample. Based on the perception of the school personnel, the results indicate moderate level of PI and SC, as well as the existence of different BP in the school context. The mediating effect of PI in the relationship between the SC and BP has been demonstrated. These results suggest that, if the SC and PI are improved, it could be an effective strategy to enhance the social functioning of students in the school context. This study thus contributes to a comprehensive empirical analysis of how PI can improve the relationship between the SC and the BP of Portuguese students.