Summary Obesity in adolescents has a serious impact later in life in the form of disturbances in health and wellbeing. We aimed to evaluate the prevalence of overweight and obesity (Ow/Ob) in Saudi adolescents and to construct an ecological model of social determinants (SDs) of Ow/Ob and evaluate current evidence of their effect on Saudi adolescents. A systematic review of literature reported up until 31 December 2018 on Ow/Ob and factors that can influence them in Saudi adolescents was conducted. Fifty‐one studies with n = 97 666 adolescents (55.6% males) were reviewed. The prevalence of Ow/Ob started off high and continued to increase over time. Most of the 49 reviewed SDs reports, from 19 studies, showed positive association between SDs constructed ecological model and Ow/Ob in Saudi adolescents. The prevalence of Ow/Ob among adolescents is a major public health problem in Saudi Arabia, is growing at an alarming rate and SDs play a significant role in this problem, and should be considered in all strategies targeting it. The constructed ecological model for SDs of Ow/Ob in adolescents can serve as a useful exploratory tool that helps investigating the multi‐faceted aetiology of adolescent Ow/Ob and facilitates the development of effective intervention and prevention programmes.