In order to study mechanical behaviors of the shear bond of concrete filled steel tube (CFST), analyze shear stress distribution and establish the relationship between shear stress and bond-slip of the shear bond, tests on 15 specimens of concrete filled circular steel tube (CFCST) and 5 specimens of concrete filled rectangular steel tube (CFRST) were carried out. The test results show that strain distribution of the steel tube was triangle along the longitudal direction and the bond shear stress distributes homogeneously. All specimens had similar bond-slip curves and the shear bond strength of CFCST was greater than that of CFRST. Based on the test results, the relationship between shear stress and bond-slip of the shear bond, was established. The shear bond strength of CFST was not considerably affected by the concrete strength, but it increased with the concrete ages and the length to diameter ratio and decreases with diameter to thickness ratio (or width to thickness ratio) of the steel tube.