This report provides information on 14 behavioral and nutritional factors, needed for stomach cancer prevention programs.PubMed, Web of Science, and Scopus databases were searched until December 2018. The reference lists were screened too. Observational studies addressing the association between stomach cancer and behavioral factors were enrolled. The heterogeneity between studies was investigated using Chi2, Tau2, and I2 statistic. The likelihood of publication bias was explored using Begg's and Egger's tests and Trim & Fill analysis. The effect szie were expressed as the odds ratio (OR) with 95% confidence intervals (CI) using a random-effects model.Of 52,916 identified studies, 232 were eligible involving 33,831,063 participants. The OR (95% CI) of factors associated with stomach cancer was as follows: H. pylori infection 2.56 (2.18, 3.00); currently smoking 1.61 (1.49, 1.75); formerly smoked 1.43 (1.29, 1.59); currently drinking 1.19 (1.10, 1.29); formerly drank 1.73 (1.17, 2.56); overweight/obesity 0.89 (0.74, 1.08); sufficient physical activity 0.83 (0.68, 1.02); intake of fruits ≥3 times/week 0.48 (0.37, 0.63); intake of vegetables ≥3 times/week 0.62 (0.49, 0.79); using pickled vegetables 1.28 (1.09, 1.51); black tea 1.00 (0.84, 1.20); green tea 0.88 (0.80, 0.97); coffee 0.99 (0.88, 1.11); using fish ≥1 time/week 0.79 (0.61, 1.03); using red meat ≥4 times/week 1.31 (0.87, 1.96), and high salt intake.This meta-analysis provided a clear picture of behavioral and nutritional factors playing pivotal roles in developing stomach cancer. These results may be utilized for ranking and prioritizing preventable risk factors to implement effective prevention programs.