Background: This paper aims to assess the impact of antibiotic therapy management by clinical pharmacists on rational drug use (RDU) in the perioperative period of patients receiving retinal detachment surgery in China from the perspective of prescription structure. Methods: In this study, a retrospective study was used to compare the differences in the RDU between 233 patients (the experimental group) receiving medical treatment and 210 patients (the control group) without clinical pharmacist intervention. The data were collected with a set of indicators adjusted from the core medication use indicator proposed by the World Health Organization and the International Network of Rational Use of Drugs according to the background of China. Results: There were significant differences in average number of drugs per prescription (19.7 and 20.8, P = 0.001), percentage of drugs on the reimbursable list (98.32% and 72.4%, P = 0.003), and average treatment expenditure per prescription (555.3 yuan and 707 yuan) between the experimental group and the controlled group, while average number of antibiotics per prescription (4.2 and 4.3, P = 0.114), average number of injections per prescription (12.02 to 11.96, P = 0.804) were not changed significantly. Conclusions: More efforts are needed to improve the effectiveness of the antibiotic therapy management by clinical pharmacist on rational drug use, meanwhile the objective of cost-saving should be included in the service pattern of clinical pharmacy services.