This invention relates to a molding material composed of a liquid thermosetting resin composition containing styrene monomer as a cross-linking component thereof and chopped glass fiber strands which can give a large molded product having high impact strength in high productivity and a method for manufacture thereof characterized by using glass fiber strands such that the number of glass filaments used in the glass fiber strands falls in the range of 600 to 1,400 per strand, the amount of a binder deposited on the glass fibers is not less than 1.0% by weight, and the percentage of styrene monomer insoluble binder falls in the range of 40 to 90% by weight.