In this study, a method called three-dimensional meshed infrared thermography (3D MIT) was developed to visualize the volumetric temperature of air using an infrared camera. The main operating principle of the proposed method is to image the spheres using an infrared camera and processing the images with computer software to obtain the volumetric temperature distribution. For the correct implementation of the method, an equation is proposed to determine the distance between the thermal target and the measurement target placed in the flow to be examined. The proposed method was compared with conventional measurement screen methods, namely those using a plane target and a high-porosity target, via particle image velocimetry (PIV) in terms of flow effects. The temperature measurement capability of the proposed method is presented in comparison with the results of thermocouple and conventional measurement screen-based measurements recorded using a jet flow. In addition, the volumetric temperature isosurfaces obtained via the 3D MIT method of a jet flow were compared with the volumetric velocity isosurfaces obtained via the PIV method in terms of the flow structure.