Objective: For patients with hypertension complicated with diabetes mellitus, their health risks are not a simple sum but present complex interactive effects. Clarifying the clinical characteristics of such patients is the key to solving this medical problem. Methods: From June 2023 to June 2024, this study conducted a comparative study on 100 patients with hypertension complicated with diabetes mellitus and 100 patients with hypertension alone. By retrospectively analyzing clinical data of patients, the differences in disease manifestations, complication occurrence, and treatment effects between the two groups were explored in depth, and the unique challenges and treatment difficulties faced by patients with hypertension complicated with diabetes mellitus were identified. Results: Hypertensive patients with concurrent diabetes had more difficult blood glucose and blood pressure control, and were more prone to severe complications such as cardiovascular lesions and renal damage. Conclusion: The clinical characteristics and treatment needs of patients with hypertension complicated with diabetes mellitus are different from those with hypertension alone, and disease management should be more refined and personalized.