In this paper, curing process monitoring of vacuum infusion molding process (VIMP) based on FBG for glass fiber reinforced vinyl resins was studied. In the experiment, three kinds of sensors were embedded in the composites. Excursion of the wavelength and temperature was tested in the whole curing process. Reflected power was tested by spectrometer in the molding process, the gel point was tested. In addition, 3-point bending test of composites which FBG was embedded in was done. Results showed that FBG could be exactly reflecting the relationship of stress and strain in bending state of composites.