Purpose: Physical inactivity in Saudi Arabia is a growing challenge to public health. This study aimed to define the relationship between the physical activity level (PAL) and adult Saudi healthrelated quality of life (HRQoL). Methods: Participants of this study were 100 Saudi adult aged from 18 -70 years. The 36-Item Short-Form Health Status Survey (SF-36) was used to measure the participant's HRQoL. The SF-36 is comprised of 8 domains. The electronic version of the General Practice Physical Activity Questionnaire was used to categorize participants in terms of physical activity level into; inactive, moderately inactive, moderately active, and active. Descriptive and inferential statistical tests were used to treat the collected data. Results: Results showed that only 17% of the Saudi adults had active PAL. The PAL had significantly positive relationship with 4 domains of HRQoL including: physical functioning (P = 0.004), role limitations caused by physical health problems (P = 0.048), vitality (P = 0.009), and general health (P = 0.044). Results also confirmed that the younger the subject, the higher the PAL (P = 0.0001) and the better the HRQoL. This is true for all domains except the role limitations caused by emotional problems and emotional wellbeing. Conclusion: The poor physical activity level of adult Saudi negatively impacts their HRQoL.