The covalent Bruton’s Tyrosine Kinase (BTK) inhibitor ibrutinib is highly efficacious against multiple B-cell malignancies. However, it also has off-target effects and multiple mechanisms of resistance, including the C481S mutation. We hypothesized that small molecule-induced BTK degradation might be able to overcome some of the limitations of traditional enzymatic inhibitors. Here, we demonstrate that BTK degradation results in more durable suppression of signaling and proliferation in cancer cells than BTK inhibition and that BTK degraders are able to efficiently degrade BTK C481S. Moreover, we generated DD-03-171, an optimized lead compound that exhibits enhanced anti-proliferative effects on mantle cell lymphoma (MCL) cells in vitro as well as efficacy in a patient-derived xenograft model of MCL. These data suggest that targeted BTK degradation is an effective therapeutic approach in treating MCL and overcoming ibrutinib resistance, thereby addressing a major unmet need in the treatment of MCL and other B-cell lymphomas.