Crawling-type adenocarcinoma (CTAC) is being increasingly recognized as a distinct histological subtype of early gastric cancer (EGC), characterized by irregularly fused glands with superficially bland cytologic atypia and a propensity for extensive lateral intramucosal spread.Although CTAC often mimics nonneoplastic lesions such as intestinal metaplasia, its biological behavior differs substantially from other differentiated-type adenocarcinomas. Notably, when CTAC invades the submucosa, the invasive component often exhibits a poorly differentiated or poorly cohesive carcinoma morphology. Thus, CTAC poses substantial challenges in accurate preoperative diagnosis, margin delineation, and complete removal during endoscopic submucosal dissection. This review synthesizes available evidence regarding the morphological, molecular, and clinical features of CTAC, emphasizing diagnostic challenges and the clinical implications of its “crawling” lateral growth pattern. It also highlights future directions, including the need for standardized diagnostic criteria and the development of CTAC-specific risk prediction tools for optimizing endoscopic resection.