In order to to solve the problems of large dead zones and high resistance of the shell-and-tube heat exchanger with segmental baffles,a novel shell-and-tube heat exchanger with vertical layout louver baffles was proposed. The three-dimensional numerical model of the heat exchanger with vertical layout louver baffles was established, and its flow structure, heat transfer, and resistance performance were investigated. The three-dimensional flow field and temperature distribution of the shell-and-tube heat exchanger with vertical layout louver baffles were obtained. The heat transfer and resistance performance were compared with those of traditional heat exchanger with segmental baffles, and the influence of the angle of the baffles on the performance of the heat exchanger was analyzed in detail. The results show that the flow field in the shell side of the heat exchanger with vertical layout louver baffles is evenly distributed. Compared with the heat exchanger with segmental baffles, the heat exchanger with vertical layout louver baffles has less dead zone, lower flow resistance, and the pressure loss in shell side is decreased by 10.06%-45.10%. The heat transfer coefficient per unit pressure drop of the heat exchanger with vertical layout louver baffles is increased by 38.62%-51.43% for the 45° louver baffles.