Uveal melanoma (UM) is the most common eye cancer in adults, with a poor prognosis due to limited effective therapies. Cannabinoids, such as cannabidiol (CBD), have demonstrated antitumor effects in various cancers, making them potential candidates for the treatment of UM. This research investigated the anticancer potential of 12 newly synthesized CBD, cannabigerol (CBG), and their derivatives on OCM-1 and OCM-3 human uveal melanoma cell lines. Determination of IC50 values using MTT cell viability assays identified six potent derivatives, with CBD being the most effective at killing cancer cells. Modified CBG derivatives also exhibited improved antiproliferative effects compared to unmodified CBG. These findings suggest cannabinoids, especially CBD, as promising treatments for UM and provide a foundation for future research into their molecular mechanisms.