Abstract Silicon photomultipliers are devices widely used and have direct applications in multiple scientific fields. Currently, the Universidad Antonio Nariño, Colombia, finance the research project Characterization of the coherent structures in the edge region of the plasma column in the TCABR tokamak using Langmuir probes in collaboration with Universidade de Sao Paulo, Brazil. In this project, we research plasma, and recently, we proposed a silicon photomultiplier to measure X-ray emissions from the plasma column. In this application, we have to know specific characteristics of silicon photomultiplier in behavior controlled conditions to establish its possible changes during exposure to radiation of plasma; one of silicon photomultiplier characteristics more important is gain due to its temperature dependence that generates disturbances on its response. To characterize the silicon photomultiplier in controlled conditions, we developed an analog integral proportional temperature automatic control system for the control of a silicon photomultiplier characterization setup that lets temperature variations from room temperature to 50°C reaching reference temperature in 1 minute with a steady state error less than 2% and overshoot of 5.53%.