Objective: To investigate the risk factors for gastric cancer in young people under 40 years of age in Guangzhou area. Methods: A hospital-based case-control study with 1:1 matching was carried out, which enrolled 59 gastric cancer patients ≤40 years old in case group and 59 healthy adults ≤40 years of age in whom gastric cancer could be excluded were in control group. A self-designed questionnaire was used to obtain information on demographics, dietary habit, lifestyle, genetic factors, medical history, helicobacter pylori (Hp) infection and psychological factors from the subjects, and then the risk factors for gastric cancer were screened by univariate and multivariate conditional Logistic regression analysis. Results: Multivariate conditional Logistic regression analysis showed that fried or grilled food consumption (OR=3.552, 95% CI=1.066–11.840), pickled food consumption (OR=4.067, 95% CI=1.171–14.127), excessive drinking (OR=11.369, 95% CI=1.029–125.589), history of chronic gastritis and peptic ulcers (OR=6.500, 95% CI=1.625–25.996), history of gastric cancer in the first-degree relative (OR=29.664, 95% CI=2.368–371.576), type A blood (OR=4.962, 95% CI=1.344–18.320), Hp infection (OR=8.376, 95% CI=2.035–34.470) and low mood or depression (OR=7.981, 95% CI=1.098–58.020) were risk factors for occurrence of gastric cancer in young people (all P<0.05). Conclusion: Occurrence of gastric cancer in young people in Guangzhou area is associated with a number of factors, and those who have the above risk factors should change their eating habits and lifestyle behaviors, and be vigilant in preventing the occurrence of gastric cancer.