The paper investigates experimentally the thermal performance and flow resistance of two-phase flow shell-and-tube heat exchangers (STHEs). STHE is configured with flat surface baffles (FSB), 4 mm amplitude-20 mm pitch sinusoidal baffles (SB), and 2 mm amplitude-20 mm pitch SB. The heat exchangers have the same geometrical design and tube count, with the exception of the baffles. The working fluids in the shell and tube side are hot water and cold air-water mixture, respectively. During the experiment, the hot water flow rate ranged from 1.63 to 2.718 kg/s, while the cold air-water mixture flow rate was set at constant value of 2.14 kg/s. The results show that the Nusselt number and overall heat transfer coefficient were highest and lowest in STHE with 2 mm amplitude-20 mm pitch SB and STHE with 4 mm amplitude-20 mm pitch SB, respectively, in comparison to STHE with FSB. When compared to STHE with FSB, and STHE with 4 mm amplitude-20 mm pitch SB, the STHE with 2 mm amplitude-20 mm pitch SB shows improvement in Nusselt number of about 36% and 21.44%, respectively. The two SB heat exchangers had lower Euler values, which indicates that their flow resistance is lower than that of STHE with FSB. Compared to STHE with FSB, there is a reduction of approximately 36% and 19%, respectively, for Euler’s values for STHE with 2 mm amplitude-20 mm pitch SB and 4 mm amplitude- 20 mm pitch SB. This study demonstrates that the use of SB in the shell side of a twophase flow STHE tremendously improves thermal performance without a corresponding increase in shell side flow resistance or pumping power. Hence, energy saving and improved heat transfer capacity are possible with SB type heat exchanger.