In recent years, FRP (Fiber Reinforced Polymer) bars have been used more and more widely in concrete structures instead of steel bars. Unlike the latter, FRP bars have the characteristics of anisotropy, heterogeneity and different surface forms, which lead to the different bond mechanisms between FRP bars and concrete. In order to fully understand the bond behavior, a database of 342 pull-out test specimens was set up. The influence of various factors on the bond behavior was analyzed. The viewpoints that there was no consensus were supplemented and discussed. The effects of high temperature, freeze-thaw cycle and electrolyte solution on the bond behavior of FRP bars and concrete were also analyzed. In addition, the predictive accuracy of the commonly used bond-slip constitutive models were checked. Based on the established test database, a new expression of the rising section of the bond-slip constitutive model was set up.