In this research, the effect of bonding temperature on the microstructure and mechanical properties of Inconel 939 super alloy by transient liquid phase bonding method. For this purpose, the middle layer of MBF20 with a thickness of 50 microns and three temperatures of 1060 °C, 1120 °C, 1180 °C and a time of 45 minutes have been used. In order to evaluate the microstructure, a scanning electron microscope equipped with an elemental analysis system has been used. Vickers hardness test and shear strength test have been used to evaluate the mechanical properties. The research findings showed that with increasing temperature from 1060 °C to 1120 °C, the width of the athermal solidification zonedecreased from 38µm to 35µm and with increasing temperature at 1180 °C, the athermal solidification zone was completely removed and isothermal solidification zone was replaced. In addition, with increasing temperature, the hardness in the joint center decreases and the shear strength increases.