Heat exchangers are one of the most important and widely used equipments in the industry, and for this reason, investigating their Thermal-Hydraulic Performance (THP) is of interest to researchers. In this study, by using the Computational Fluid Dynamics (CFD) technique, the THP of the straight channel, serpentine channel (SC), serpentine channel equipped with twisted-tape insert (SCT), and serpentine channel equipped with triple-channel twisted-tape insert (SCTT) was studied. The study was carried out for channels with a hydraulic diameter of 0.02 m and flow path length of 2.153984 m in turbulent flow with Reynolds numbers (Re) between 10000 and 30000. In all the channels, the wall temperature was supposed to be constant at 363 K, and the liquid water was selected as the studied fluid, whose temperature at the entrance of the channels was determined to be 298 K. According to the results, the thermal performance of the SCTT channel was better than the other channels, but instead, the hydraulic performance of the SC channel was more appropriate.