Cannabis has been used for millennia to treat a multitude of medical conditions including chronic pain. Osteoarthritis (OA) pain is one of the most common types of pain and patients often turn to medical cannabis to manage their symptoms. While the majority of these reports are anecdotal, there is a growing body of scientific evidence which supports the analgesic potential of cannabinoids to treat OA pain. OA pain manifests as a combination of inflammatory, nociceptive, and neuropathic pain, each requiring modality-specific analgesics. The body’s innate endocannabinoid system (ECS) has been shown to ameliorate all of these pain subtypes. This review summarizes the components of the ECS and details the latest research pertaining to plant-based and man-made cannabinoids for the treatment of OA pain. Recent pre-clinical evidence supporting a role for the ECS to control OA pain is described as well as current clinical evidence of the efficacy of cannabinoids for treating OA pain in mixed patient populations.