Objective To explore the correlation between abnormal body fat and gastric cancer and guide health management. Methods The physical examination results of 1 341 patients who underwent physical examination in physical examination department of The First Affiliated Hospital of Guangzhou University of Chinese Medicine from January 2018 to December 2019 were collected and retrospectively analyzed. The correlations among pepsinogen (PG), body fat percentage, body fat related indexes and influencing factors of body fat were analyzed by t test and linear correlation analysis according to age, sex and Helicobacter pylori infection. Results Average body fat percentage was higher than normal standard, and the ratios of pepsinogen I (PGI) and PGI/II (PG-Ratio) in male group were higher than those in female group (P<0.05). The total cholesterol (TC), low-density lipoprotein (LDL-C), blood glucose (GLU), PGI and PGII in men and women aged 41 to 70 years were higher than those in men and women aged 16 to 40 years (P<0.05). Body fat percentage, PGI and PGII, BMI, TC, TG, LDL-C and GLU were increased, while PG-Ratio was decreased in postmenopausal women compared with premenopausal women (P<0.05). The TC, LDL-C, PGI and PGII in Hp-positive patients were higher than those in Hp-negative patients, and the PG-Ratio in Hp-positive group was lower than that in Hp-negative group (all P<0.05). PG I and PG II were positively correlated with age regardless of sex or Hp infection (P<0.05). There was a significant negative correlation between PG and body fat percentage in male and postmenopausal women (P<0.01), but no correlation between PG and body fat percentage in premenopausal women (P>0.05). There was a significant negative correlation between PG-Ratio and body fat percentage in Hp-positive patients (P<0.01). One year later, 209 cases had gastrointestinal discomfort. The incidence of precancerous lesions was higher in males (13.73%) than in females (6.54%) (P<0.05). Conclusion Abnormal body fat may easily infect Hp, touch the inflammatory-cancer pathway, and increase the risk of gastric cancer. This relationship is more pronounced in men than in women. Elderly men infected with Hp and high body fat may be at high risk for gastric cancer