Shear connectors are the important detailings affecting the mechanical properties of GFRP-concrete composite beams/decks. Rectangular rib and T-type rib GFRP shear connectors are put forward to improve the interfacial bond properties between GFRP and concrete. Eight push-out tests are conducted to evaluate the mechanical behaviors of two rectangular perforated rib GFRP shear connectors and three T-type perforated rib GFRP shear connectors, as well as three T-type rib GFRP shear connectors. The failure patterns, ultimate bearing capacities, load-slip behaviors and load-strain regularities are obtained by contrast tests. Results show that T-type perforated rib GFRP shear connectors show higher strength and better ductility than rectangular perforated rib GFRP shear connectors, and T-type perforated rib GFRP shear connectors show higher strength and better ductility than T-type rib GFRP shear connectors. An empirical equation to predict the ultimate shear resistance is proposed and validated by the experimental data. Idealized load-lip models and equations to predict the load versus slip relationship for all specimens are proposed. Curve fittings are performed to find fitting parameters for all tested specimens and the results show a very good correlation with those of the experiments. An empirical equation to predict the shear rigidity is proposed.