To realize the measurement of the biological dose in wide range, this paper dis discribes a biodosimeter based on the radiation damage effect of proteins (bovine serum albumin, bovine hemoglobin, and casein) and completed a dosimeter response study under γ radiation. Gafchromic film was used to measure the protein solution dose, and the solution dose was obtained by combining the film dose and the dose conversion factor calculated by Monte Carlo N Particle Transport Code (MCNP). The Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis technology (SDS-PAGE) was used to characterize the damage degree of proteins. By selecting the appropriate fitted range and weighted mean dose method, an accurate measurement of the film dose was realized. In the investigation of the irradiation damage effect of proteins, the damage degree of proteins gradually increased with increasing dose according to the exponential function. Different proteins have various response modes. For the three studied proteins, the protein with greater solution concentration were more difficult to degrade. The dose rate also influenced the damage effect of proteins. Damage degree was smaller at higher dose rates. A dose measurement from 2.3 to 2555.7 Gy was achieved by adjusting the concentration of the bovine serum albumin, and wide-range dose measurements is possible by changing protein types and the solution concentration. The novel dosimeter could realize wide-range biological dose measurement and prompt further research on the biological effect of radiation, given the great significance in the determination of the biological effects and in the health assessment of irradiated bodies.