Objective: To describe the physical activity (PA) profile and its determinants among attendants of primary healthcare (PHC) centers in Abha City, Saudi Arabia. Subjects and methods: A cross-sectional study design was followed to include 404 Saudi adults aged 19-65 years who attended PHC centers in Abha City. A self-administered questionnaire was designed by the researchers and was used for data collection. It consisted of three parts, i.e., personal characteristics, participants' PA assessment by the Arabic short form of the International Physical Activity Questionnaire (IPAQ), while the third part included inquiry about barriers against PA. Results: Most participants (80%) reported low level of PA, whereas 17.1% reported moderate PA. High level of PA was reported among only 12 participants (3%). Vigorous physical activities were practiced by only 4% of participants, whereas moderate physical activities were practiced by only 3%, and walking was practiced by 49.8%. Regarding duration of sitting (minutes/day), 40.3% reported sitting periods more than 360 minutes/day. Moderate and high physical activities were more practiced by males than females (21.5% and 3.4% versus 12.6% and 2.5%, respectively, p=0.046). Barriers to PA included unavailability of suitable places to exercise, being not sure of the ability to exercise efficiently, believing that exercise is hard work, and being embarrassed to exercise. Conclusions: Most Saudi adults attending PHC centers in Abha City have low level of PA. Males have significantly higher PA than females. There are several barriers against PA. Overcoming these barriers will contribute to improvement in PA among the Saudi population.