The aim of this work is to improve the tribological properties of epoxy composite as water pipeline internal coating material, against water jet erosion wear analysis and investigating the effect of adding Multi Wall Carbon Nanotubes (MWCNT) to epoxy with different weight percentages (0, 0.1, 0.2, and 0.3). Then, morphologies, erosion resistance, and tensile strength are assessed. To simulate how the epoxy coating would erode under water jet contact, water cutting equipment was utilized. The total test time was 5 minutes. Analyzing and revealing the damage behavior and damage mechanism of coating, a damage evolution curves was developed by using a digital microscope and a scanning electron microscope (SEM) to evaluate the damage morphology of samples at different stages of damage. In the experimental work, steady-state erosion values of the epoxy coating have been evaluated at different impact angles (15◦, 30◦, 45◦ and 60◦) and different impact distances (100 and 200 mm), with constant water jet velocity of 5 m/s Compared with pure epoxy, the results showed that the elongation characteristics improved by 46.67% and the tensile strength improved by 66.7%. Improved interfacial contacts and efficient stress transmission result in improved tensile and elongation properties when MWCNTs are added. Meanwhile, the experimental results showed that 0.3 wt. % MWCNT/EP composite indicated the maximum erosion resistance at the impact angles ranged from 15◦ to 30◦ and impact distance of 200 mm, whereas the EP pure coating material exhibited the maximum erosion values at the impact angle of 45◦ and 60◦ and impact distance of 100 mm.