Gastric cancer (GC), a multifaceted and highly aggressive malignancy, represents challenging healthcare burdens globally, with a high incidence and mortality rate. Although endoscopy, combined with histological examination, is the gold standard for GC diagnosis, its high cost, invasiveness, and specialized requirements hinder widespread use for screening. With the emergence of innovative technologies such as advanced imaging, liquid biopsy, and breath tests, the landscape of GC diagnosis is poised for radical transformation, becoming more accessible, less invasive, and more efficient. As the non-invasive diagnostic techniques continue to advance and undergo rigorous clinical validation, they hold the promise of significantly impacting patient outcomes, ultimately leading to better treatment results and improved quality of life for patients with GC.