Political well-being refers to an individual’s trust, adaptability, political efficacy, active participation, and cognitive flexibility in political matters, and plays a critical role in influencing political behaviors, including tendencies toward political aggression. The present study aimed to develop and validate the Political Well-Being Scale (PWBS) and to examine its relationship with political aggression. This applied-developmental research employed a descriptive–psychometric design. The statistical population consisted of university students in Iran who were active on social and media networks during the 2024–2025 academic year. Using an online call and convenience sampling, 720 participants were selected. The research procedure included item generation, assessment of content and face validity, exploratory and confirmatory factor analyses, criterion-related (convergent and divergent) validity, and reliability evaluation. Data were analyzed using SPSS-24 and AMOS-24 software. Exploratory factor analysis confirmed a 17-item scale with three components—Political Trust, Political Efficacy and Participation, and Political Flexibility and Tolerance—accounting for 69.72% of the total variance. Confirmatory factor analysis indicated good model fit (χ²/df=1.21, RMSEA<.08). The composite, internal consistency, and test–retest reliabilities of the total scale were .93, .93, and .74, respectively. Significant correlations of political well-being with general health and political aggression supported the scale’s convergent and divergent validity. Overall, the Political Well-Being Scale demonstrated satisfactory psychometric properties and provides a reliable measure for assessing political well-being. Findings suggest that political well-being plays a significant role in political aggressive behaviors and merits further investigation in future research.