As we know that a shell and tube heat exchanger is designed where high pressures and high pressure differences between the fluids relative to the environment are applied. These exchangers are generally built of a bundle of round tubes mounted in a cylindrical shell with the tube axis parallel to that of the shell. There is considerable flexibility in the design because the core geometry can be varied easily by changing the tube diameter, length and arrangement. One fluid flows inside the tubes, and other flows across and along the tubes. In this project, the hot fluid will be cooled using seawater with the help of shell and tube heat exchanger. A characteristic of heat exchanger design is the procedure of specifying a design heat transfer area and pressure drops and checking whether the assumed design satisfies all requirement or not. The purpose of this project is how to design the heat exchanger which is the majority type of liquid-to-liquid heat exchanger. General design considerations and design procedure are also illustrated in this project.