There has been significant increase in use of glass fibre reinforced composites as structural materials in naval mine countermeasure surface ships. Sea mines when detonated emit underwater shock waves, which could impart severe loading to naval ship structure; there are attempts to model the response of a ship structure to this loading. For the model to be accurate & useful material property data determined experimentally by taking different weight percentage of glass fibers (E-300, mat form) with epoxy resin & comparison with fly ash reinforced composite. Specimens in the form of cube of size 10X10X10 (mm’s) are used & results are presented. Fracture behaviour of composite can also be studied using SEM. SEM analysis is done to observe distribution of fly ash particles in matrix, resin fly ash interface, glass fibre matrix interface, glass fibre distribution etc,.