Water immersion experiments were normally used to observe the influence of water on the physical properties of hemp fiber strengthened unsaturated polyester laminates (HFRUPE). HFRUPE composite samples with fiber volume fractions of 0, 0.20, 0.25, 0.29, and 0.35 were manufactured. In order to perform moisture absorption test, specimens were submerged in a deionized water tub by maintain the temperatures such as ambient temperature to 100 °C for varying amounts of time. Together with dry composite specimens, the ductile and bending characteristics of specimens submerged in water and exposed to both aging regimes were assessed and compared. Since natural fibers possess high cellulose content, the percentage of water uptake rose as the fiber volumetric fraction increased. It was found that, as much as the proportion of moisture uptake increased, the HFRUPE specimens’ tensile and flexural qualities decreased significantly.