Abstract: Perforated glass fiber reinforced polymer (GFRP) ribs is a common interfacial shear connector in GFRP-concrete hybrid beams. Fifteen double shear tests, divided into five groups, were performed to study the shear behavior of perforated GFRP ribs. Test parameters included the griding depth on GFRP profiles (0.5 mm/1.0 mm), the existence of penetrating GFRP bars, the diameter of penetrating GFRP bars (9.5 mm/13.0 mm), and concrete strength (C30/C50). Test results show that the failure modes of specimens with a grinding depth of 0.5 mm and 1.0 mm on GFRP profile are classified into debonding failure and shearing failure of perforated GFRP ribs without broken of penetrating GFRP bars and concrete wedge, respectively. The shear force-slip curves for perforated GFRP ribs are composed of micro-slippage section and slippage section. The shear stiffness of specimens with 1.0 mm grinding depth on GFRP profiles is higher than specimens with 0.5 mm grinding depth. In addition, the shear stiffness increases with the increment in concrete strength and the existence of penetrating GFRP bars. The shear resistance of specimens with 1.0 mm grinding depth on the GFRP profile is about 44.82% higher than that of specimens with 0.5 mm grinding depth on the GFRP profile. And the shear resistance of specimens with penetrating GFRP bars is about 20% higher than that of specimens without penetrating GFRP bars. The concrete strength and diameter of penetrating GFRP bars have little effect on the shear capacity of perforated GFRP ribs. Finally, on the basis of the maximum shear stress criterion, the critical shear failure position on perforated GFRP ribs is derived and a calculation approach for shear capacity under debonding failure is proposed, which is in good agreement with the experimental results.