One of the most prevalent malignant tumors worldwide, stomach cancer still has a high incidence and fatality rate in China, and the number of young people developing early-onset gastric cancer is steadily increasing. The 5-year survival rate of stomach cancer is typically 30%-35%, the prognosis is bad, the patients' quality of life is low, and the progression of advanced gastric cancer cannot be effectively managed despite the use of surgical surgery, chemotherapy, and other medicines. We urgently need molecular biomarkers with high specificity and sensitivity to increase the early gastric cancer detection rate, extend patient survival, and improve patient quality of life. The initial diagnosis of gastric cancer primarily depends on gastroscopy and biopsy, and invasive procedures cause significant discomfort to patients. Similar to this, treating advanced and metastatic stomach cancer is a pressing issue that requires attention. More and more immune checkpoint molecules have been discovered, and corresponding inhibitors are gradually being applied to clinical diagnosis and treatment. Recently, some non-coding RNAs have begun to be used as new targets for the treatment of gastric cancer. Some non-coding RNAs are highly present in the serum or urine of gastric cancer patients and can be used as diagnostic markers or prognostic indicators. Many clinical trials targeting non-coding RNAs have also shown good therapeutic effects. In general, targeting non-coding RNAs has shown good therapeutic effects. The biomarkers for gastric cancer detection and treatment are reviewed in this article, focusing on the new non-coding RNAs used in diagnosis, prognosis, and treatment. Patients with stomach cancer should have access to more precise and efficient diagnosis and treatment choices as a result of ongoing technological advancements and thorough research.