Abstract: To investigate the bond performance between novel mechanically grooved rib GFRP bars and concrete, a central pull-out method was used to finish bond performance experiments on 27 mechanically grooved rib bars and 18 helically wrapped rib bars with diameters of 8 mm, 12 mm, and 16 mm. The differences in bond performance between the two types of FRP bars were compared and analyzed, and the influence patterns and mechanisms of bar diameter and rib-width ratio (the ratio of concave rib width to rib spacing, with three ratios of 0.3, 0.5, and 0.7 adopted in this study) on the bond performance of GFRP bars were discussed. The experimental results indicated that when rib parameters were consistent, the bond performance of mechanically grooved rib bars across all three diameters was significantly superior to that of helically wrapped rib bars, with the bond strength of mechanically grooved rib bars increasing by 26%-46% and the free-end slip decreasing by 54%-71%. Unlike traditional FRP bars, the bond strength of mechanically grooved rib bars improved with increasing diameter. As the rib-width ratio increased, the bond strength of mechanically grooved rib bars showed an upward trend, reaching its highest level when the rib-width ratio was 0.7. Based on the experimental data from this study and existing research, a predictive model for the bond strength of mechanically grooved rib GFRP bars was established, and design recommendations for anchorage length were proposed, providing a theoretical foundation for the practical application of this bars.