The purpose of our study was to evaluate Magmas as a potential target in prostate cancer. In addition, we evaluated our synthetic Magmas inhibitor (BT#9) effects on prostate cancer and examined the molecular mechanism of BT#9. A cell viability assay showed that treatment with BT#9 caused a significant decrease in the viability of DU145 and PC3 prostate cancer cells with little effect on the viability of WPMY-1 normal prostate cells. Western blot proved that BT#9 downregulated the Magmas protein and caspase-3 activation. Flow cytometry studies demonstrated increased apoptosis and disturbed mitochondrial membrane potential. However, the main mode of cell death was caspase-independent necrosis, which was correlated with the accumulation of mitochondrial and intra-cellular Reactive Oxygen Species (ROS). Taken together, our data suggest Magmas is a potential molecular target for the treatment of prostate cancer and that Magmas inhibition results in ROS-dependent and caspase-independent necrotic cell death.