An object of study is a SrBr2 vapor laser source with its emission at a wavelength 6.45 μm. This type of laser finds applications in medicine and biology. A temperature model, determining the laser medium’s temperature profile under forced convection is used in this study on the basis of quasi-stationary heat conduction equation. It was established that the working temperature can change in a wide range while the airflow velocity changes. Computer simulations that let increase of supplied electrical power for holding optimal temperature in the center of the tube were performed.