Low back pain (LBP) is a common health problem. Professions like physical therapy (PT), involving frequent lifting, bending, or standing, are at risk for developing LBP. The objective of this study was to determine the prevalence of work-related LBP and factors associated with and consequences of work-related LBP among physical therapists in Riyadh, Saudi Arabia. A self-administered online questionnaire (i.e., demographic data, history of LBP before and after working as a physical therapist, work setting, and effect on daily activities) was sent to 600 members of the Saudi PT association. Data were analyzed using the Pearson chi-square test and Mann-Whitney U test. Eighty-eight percent of potential respondents completed the questionnaire. Of these, 89.65% of the therapists reported LBP after beginning their PT practice, and 35.6% reported LBP at the time of this survey. Gender, PT specialty, and duration of contact with patients were all found to be related to LBP. The prevalence of work-related LBP among physical therapist in Riyadh was high, affecting patient care and daily activities of the therapists. Both primary and secondary prevention strategies (e.g., introduce ergonomics into PT curricula, reduce therapist stress, and promote teamwork) are needed to decrease LBP among therapists, so they can effectively care for patients.