This paper has been studied by a single fiber pull-out test about the effect of diameter and the surface treatment of glass fiber on the interfacial shear strength between fiber and matrix resin (epoxy and PE resin). Pull-out experiments have been carried out using microbonding and solution microbonding test method. The results of test were shown that, as the fiber diameter increases, the interfacial shear strength decreases regardless of the kind of fiber surface treatment, epoxy and PE resin.