Background. To investigate the intervention effect of clinical pharmacists on irrational use of proton pump inhibitors (PPIs) in clinicians. Methods. A cross-sectional study was used to through the hospital information management system survey, before intervention (July 15th, 2016, Aug 15th, 2016 and Sep 15th 2016) and dry prognosis (July 15th, 2017, Aug 15th, 2017 and Sep 15th, 2017) all the use of PPIs inpatients related information. According to the guidelines of "drug instructions" and "experts on stress ulcer prevention and treatment experts", the standard of drug use was formulated, and the use of PPIs before and after intervention was evaluated and analyzed in accordance with the standard, and the results of intervention were evaluated. Results. The total number of hospitalized patients surveyed before the intervention was 1,693, the average utilization rate of proton pump inhibitors was 27.05% and the coincidence rate was 52.40%. The total number of hospitalized patients investigated after the intervention was 2,095, the average utilization rate of proton pump inhibitors was 8.54%, and the coincidence rate was 68.16%. Before and after the intervention, there was no difference in gender ratio and age distribution, the decrease of the utilization rate and the improvements of the qualified rate after intervention were statistically significant.Conclusion. According to the standards of PPIs, clinical pharmacists strictly implement the special prescription review system and other intervention measures, which can significantly improve the level of PPIs rational clinical medication.