Following bariatric surgery, there is a crucial period, as depression can develop during this period. We aim in this study to assess the prevalence of depression and its contributing factors following bariatric surgery among adults in all regions of Saudi Arabia. This study aims to establish prevalence of depression among patients undergoing bariatric surgery in Saudi Arabia. A cross-sectional study included male and female adult patients that had bariatric surgery in Saudi Arabia. Using an online questionnaire regarding patients' sociodemographic data, medical information, and evaluation of depression after a bariatric procedure using PHQ-9. The study included 408 participants. The age group with the highest percentage is 19-30, accounting for 47.8% of the total. Females make up the majority of the respondents. Prior to the surgery, the majority of individuals fell into the higher BMI categories, with a higher number of individuals having a BMI above 40. In conclusion, the prevalence of depression among patients undergoing bariatric surgery is a crucial area of study. Age, marital status, gender, and educational level may be important factors to consider when assessing an individual's risk for depression. However, further research is needed to explore the underlying mechanisms behind these associations and to determine the potential implications for prevention and treatment strategies.