VIMP (Vacuum Infusion Molding process) is widely used because it has many advantages, such as low cost, environmental protection and suitable for holistic mould of large composite structures. Curing reaction and rheological behavior of a low viscosity epoxy resin system were studied by DSC and viscosity experiments and an optimum curing temperature was found for the resin system. Based on Dual-Arrhenius equation, a rheological model of the resin system was established, and predicted viscosity values of the resins were in good agreement with the results of the experimental results. The low viscosity processing window for the VIMP was determined by the rheological model. A GFRP laminate was fabricated by the VIMP, and the fiber volume content and mechanical strength of the laminate composites were investigated.