Lymphoma, the most common form of blood cancer, affects primarily the intricate network of tissues and organs known as the lymphatic system. Globally, it ranks among the leading causes of cancer-related deaths. Although conventional therapies have led to significant advancements, they are accompanied by adverse side effects and present challenges in cases of multidrug resistance, refractory patients, and relapses. This highlights a pressing need for innovative treatment approaches. Extensive research on the anti-lymphoma properties of natural compounds has particularly focused on marine organisms as valuable sources for potential medicinal agents. Among these, anticancer peptides have garnered attention due to their multiple beneficial effects against cancer, coupled with reduced toxicity to normal cells. This review focuses on the molecular mechanisms underlying the anti-lymphoma effects of marine peptides, examining the diverse pathways through which these peptides impact physiological processes. Key effects include modulation of cell viability, induction of apoptosis, cell cycle arrest, antimitotic activity, immunotherapeutic properties, disruption of mitochondrial function and induction of oxidative stress, cancer cell membrane destruction, and interference with microtubule stability. The review also highlights the antibody–drug conjugates (ADCs) derived from marine peptides and their synergistic effects with other anti-lymphoma medications. This knowledge should inspire future study and development of these prospective therapeutic modalities and hasten the investigation and creation of novel lymphoma remedies derived from marine sources.