The objective of this paper is to study the effect of nanofluid on the performance of the heat exchanger, as well as the heat transfer rate, coefficient of total heat transfer, friction influence and average Nusselt number, and thermal efficiency factor and has been investigated and discussed. In this work, the output heat transfer of Fe3O4/water nanofluid through shell and tube heat exchanger has been numerically investigated under laminar flow. CFD simulations with ANSYS FLUENT 2020R1 were used adopting finite volume approach to solve the governing equations. Numerical calculations were carried out for Reynolds numbers ranging from 200 to 1400, with nanoparticles as the volume fraction (0.2% and 0.35%). The results show that the augmentation in increase Nusselt number and amount of heat transfer rate and the efficiency of nanofluid at the concentration of 0.35% are approximately 19%, 25% and 12% respectively. It was observed through the results that the friction decreases as the Reynolds number increase.