Objective: To explore the effect of the pharmacy service model for hypertensive patients based on the construction of pharmacy specialty medical alliances in improving blood pressure control rate, medication compliance, and drug safety, and to provide a feasible path for the construction of the chronic disease pharmacy service system at the primary level. Methods: A randomized controlled trial was conducted. A total of 100 patients from Baimaguan Town Health Center in Luojiang District, Deyang City and the cooperative units of the medical alliance were selected from July 2025 to January 2026 and randomly divided into an intervention group and a control group, with 50 cases in each group. The control group was managed by a regular family doctor, while the intervention group, on this basis, adopted the pharmacy specialty medical alliance service model, where clinical pharmacists from tertiary hospitals guided primary pharmacists to complete individualized prescription review, medication compliance assessment, adverse reaction monitoring, and electronic drug record follow-up. The intervention lasted for 6 months to observe blood pressure control rate, MMAS-8 medication compliance, incidence of adverse reactions, and satisfaction with pharmaceutical care. Results: After the intervention, systolic blood pressure (131.5 ± 7.4 mmHg) and diastolic blood pressure (82.3 ± 5.6 mmHg) in the intervention group were significantly lower than those in the control group (137.2 ± 8.1 mmHg, 86.1 ± 6.2 mmHg) (P < 0.01); The rates of reaching the target blood pressure were 86.0% and 64.0% respectively (χ² = 6.93, P = 0.008). The MMAS-8 score of the intervention group was 7.2 ± 0.6, compared with 6.3 ± 0.8 of the control group (t = 5.96, P < 0.001), and the incidence of adverse reactions was 6.0% less than 16.0% of the control group (χ² = 4.02, P = 0.045). The satisfaction score for pharmaceutical care was 93.4 ± 5.2 points, which was higher than 85.6 ± 6.3 points in the control group (t = 6.42, P < 0.001). Conclusion: The pharmacy service model for hypertensive patients in the pharmacy specialty medical alliance can significantly improve blood pressure control rate, medication compliance, reduce the incidence of adverse drug reactions, and increase patient satisfaction. This model optimizes the collaboration mechanism between physicians and pharmacists and has significant promotion value for promoting rational drug use at the grassroots level and building a sustainable chronic disease pharmacy service system.