Background: Adolescents' possession of guns was a matter of concern even before the pandemic. It is pertinent to examine whether students continued possessing guns after schools reopened, and if so, identify factors that might have been associated with such behaviors. Towards this end, the present study examined the relationship between highschool students' experiences and their propensity to possess guns. Methods: This used responses from multiple nationally representative cross-sectional surveys of high school students from the 2019 and 2021 Youth Risk Behavior Survey (YRBS) and the 2021 Adolescent Behaviors and Experiences Survey (ABES). Gun possession within the past year was the main outcome of interest. Experiences of violence, assault, injury, and other adverse experiences were the independent variables. Bivariate and multivariate logistic regressions, adjusting for sample weights, were performed using SAS. Results: Out of a total of more than 25,000 and 38,000 valid responses, respectively in 2019 and 2021 to the question on gun possession, 4.7% and 4.2% reported carrying a gun at least once within the past year. Experiences of sexual violence, involvement in physical fight, perceived lack of safety, and being threatened/injured by weapons, were associated with higher adjusted odds of guns possession among males and females. Among ABES 2021 respondents (more than 7500), those who witnessed violence in the neighborhood were more likely to possess guns. This association was significant among males, whereas parents being informed about whereabouts was significant for females. Conclusion: This study shows that adverse experiences were associated with a higher odds of guns possession among female and male highschool students. Witnessing violent attack on someone in the neighborhood emerged as a risk factor for males. This suggests that social determinants of health as well as adverse experiences are associated with gun possession among high-school students.