Objective To investigate and analyze the disease spectrum of hospitalized naval officers and soldiers, so as to provide reference for their health management and medical support. Methods The disease spectrum of hospitalized naval officers and soldiers was analyzed based on the front page data of medical records collected from 6 hospitals in a region between 2013 and 2017. The principal discharge diagnoses of inpatients were classified and statistically analyzed according to the International Classification of Diseases (ICD)-10. Results A total of 21 177 hospitalized diagnosis and treatment data of naval officers and soldiers were included, and the top 10 diagnostic categories accounted for 85.98% (18 208/21 177). In the major diagnostic categories of inpatients, circulatory system diseases (14.79%, 3 132 cases), digestive system diseases (14.59%, 3 090 cases), respiratory system diseases (14.06%, 2978 cases), and genitourinary system diseases (9.94%, 2 104 cases) ranked the top 4. Common diseases under the top 4 major diagnostic categories included chronic ischemic heart disease (21.87%[685/3 132］), acute appendicitis (16.38%[506/3 090］), pneumonia (pathogen unspecified) (19.21%[572/2 978］), and kidney and ureteral calculus (20.77%[437/2 104］). The disease spectrum of hospitalized naval officers and soldiers of different genders and ages displayed different characteristics. Conclusion Circulating system diseases, digestive system diseases, respiratory system diseases, and genitourinary system diseases are the main types of diseases of hospitalized naval officers and soldiers. The abilities of diagnosing and treating and prevention and control education should be strengthened for the above major diagnostic categories and corresponding common diseases.