It aims to analyze the influence of hospital informatization investment, operation and management on the hospital medical benefit. The data of informatization input, hospital operation management and medical gross income of a 3-A hospital in Chongqing during 20092015 was taken as the research object, and Pearson correlation analysis found that the medical gross is related to 11 indicators (P<0.05). Then the indicators with weight values greater than 0.08 were sifted by entropy method, including hospital annual financial information (x₁), the annual outpatient per year (x₄), hospital surgery per year (x₆), annual number of patients per year (x₇), and hospital primary title number (x₁₀), and their weights are 0.190, 0.086, 0.085, 0.084, 0.084 respectively. Finally, a multi-factor regression model was established, the fitting function of the indicators (x₁, x₄, x₆, x₇, x₁₀) and medical gross income was obtained, the coefficients of determination were 0.948 8, 0.927 1, 0.994 1, 0.993 0, 0.948 1 respectively and the determination coefficient of the regression equation of medical gross income is 0.9963. 5 indicators influencing medical gross income were obtained by entropy method, and the proposed regression equation can be used for hospital informatization investment decisions, which provides a new basis for medical and health management.