Endoscopic ultrasonography (EUS) has recently gained a pivotal role in the management of gastric lymphomas, especially in the diagnostic workup. Its accuracy and reliability have overcome those of other imaging techniques, such that it represents an invaluable tool for the management of gastric lymphomas. Although this technique is operator dependent, its application in large series has proved its reliability. Thus, it has generally been considered a useful tool for providing information crucial in deciding the treatment program, especially for mucosa-associated lymphoid tissue (MALT) lymphomas, for which EUS can provide an accurate evaluation of disease extension and treatment response probability. Limited-stage disease, confined to the submucosa, has a greater probability to respond to sole Helicobacter pylori eradication. In contrast, the value of EUS in response assessment and follow-up monitoring is still debated, with discordant opinions about its reliability and clinical advantages, because normalization of the EUS findings occurs with a considerable delay compared to the histologic evaluation. In the follow-up setting, preliminary data have indicated that persistently positive EUS findings in low-grade gastric lymphoma could represent a warning for a possible relapse. However, in high-grade gastric lymphoma, such findings do not have any clinical implications.