This paper presents a study about the bond of high strength concrete with high strength steel. Fourteen pull out tests were carried out to determine the bond. The concrete strength was about 70 MPa and the steel was a 500 MPa grade. Bar diameters used were 12, 16, 20, 25, 28, 32 and 36 mm. In order to investigate the effect of cover, each test was done twice, once in a 240 mm diameter concrete cylinder and the second in a 300 mm diameter cylinder. Based on the test results a new equation representing the bond is proposed.