Background & Objectives: In patients with gastric cancer, the most frequently reported family history of cancer also involves the stomach. The aim of this study was to assess the presence of gastric precancerous lesions in first-degree relatives of patients with gastric cancer and to compare the obtained results with those of individuals with no such family history. Methods: Between 2007 and 2009, 503 consecutive persons more than 30 years old were enrolled in the study covering siblings, parents or children of patients with confirmed adenocarcinoma of stomach. The control group was made up of 592 patients who were synchronously undergoing upper gastrointestinal endoscopy for evaluation of dyspepsia without gastric cancer or any family history. All subjects were endoscopically examined. Results: The overall prevalence of Helicobacter pylori was 77.7% in the cancer relatives and in 75.7% in the control group. Chronic gastritis was found in 90.4% vs. 81.1% (P<0.001). Regarding histological findings, 37(7.4%) of the study group had atrophy vs. 12(1.7%) in the control group (P<0.001), while no difference was observed for intestinal metaplasia (20.3%vs. 21.6%, P=0.58). Dysplasia were shown in 4% of cancer relatives but only 0.4% of the control group (P<0.001). There was no gender specificity. Conclusions: Findings of our study point to great importance of screening in relatives of gastric cancer patients in Iran.