BACKGROUND: Prosocial behaviors refer to a variety of voluntary actions intended to benefit others and the society. They have consistently proven their capacity to promote individuals' well-being and personal development. Nevertheless, these constructs remain largely underexplored in the Arab world. Providing validated measures of prosocial behaviors in the Arabic language for the Lebanese population could direct research attention towards assessing these behaviors and their promoting factors, thereby enhancing positive psychology. In this regard, we aimed to psychometrically validate the Standard Arabic-translated versions of the Perceived Social Competence scale (PSCS) and Prosociality Scale (PS) among a sample of Lebanese adults. METHODS: A total of 403 Lebanese adults (27% men and 73% women) completed an online questionnaire containing the PSCS and PS, as well as the Buss-Perry aggression questionnaire-short form, the Jong-Gierveld loneliness scale, and the depression anxiety stress scale. RESULTS: Both of the PSCS and PS yielded a unidimensional factor structure and demonstrated high levels of composite reliability, with McDonald ω values of 0.83 and 0.95, respectively. The analysis also supported configural, metric, and scalar invariance across gender for the two scales. Convergent validity was evidenced by a high correlation between the PSCS and PS, both measuring prosocial behaviors. In addition, weak and/or non-significant relations between prosocial behaviors and non-theoretically relevant variables (i.e., aggression, loneliness, and psychological distress) provided evidence for the divergent validity of both scales. CONCLUSION: Our study cautiously suggested that the Standard Arabic versions of the PSCS and PS are psychometrically valid for measuring prosocial behaviors. This study should prompt further research in the field of social competence/prosocial behaviors for the sake of promoting positive psychological interventions in Lebanon. Future research should prioritize the inclusion of more diverse samples, encompassing a wider range of sociodemographic characteristics, in order to enhance the generalizability of these findings to the broader Lebanese population.