According to the pull out tests of 20 specimens, the bond slip mechanism between light gauge steel and expanded polystyrene(EPS) concrete was investigated. The effects of cover thickness, concrete strength and bonded length were studied. Results show that compared with normal reinforced concrete, bond strength between light gauge steel and EPS concrete is lower. Ultimate bond strength is improved with the increase of cover thickness and concrete strength, while bonded length shows little effect on the bond strength. Based on the test results, a three stage bond slip model is proposed to represent the bond behavior of light gauge steel in EPS concrete, which agrees well with the test results.