Introduction. The prevalence of chronic atrophic gastritis and intestinal metaplasia based on samples from third-level hospitals, may overestimate their frequency. Objetive. To estimate the frequency of premalignant histological lesions of the stomach in a second-level hospital. Material and methods. Observational, retrospective, descriptive, cross-sectional, epidemiological study. It was conducted with patients who had already undergone diagnostic upper digestive endoscopy, regardless of the clinical reason. Patients with gastrointestinal bleeding, tumors or without biopsy were excluded. Results. A total of 4454 cases were reviewed, of which 115 (2.6%, CI 2.2-3.1) had chronic atrophic gastritis. Compared to non-atrophic gastritis, the presence of chronic atrophic gastritis was more frequent in older adults (43.5% vs. 24.9%; p < 001) and in those with dyspepsia symptoms (35.7% vs. 19.9%; p < 0.001); and less frequent in economically active population (47.8% vs. 64.9%; p < 0.001). Among patients with chronic atrophic gastritis, nearly twice as many tested positive for Helicobacter pylori (47.8% vs. 25.6%; p < 0.001). Helicobacter pylori infection nearly tripled the risk of developing chronic atrophic gastritis (Odds Ratio 2.65; p < 0.001). Conclusion. In a second-level hospital, the prevalence of premalignant histological lesions is significantly lower than that reported by local studies conducted in third-level hospitals. The presence of chronic atrophic gastritis was associated with older age, indication for upper digestive endoscopy for dyspepsia, and Helicobacter pylori infection; while the indication for regurgitation was associated with its absence.