Abstract: Experiment on the performance of ceramsite lightweight aggregate concrete ( LWAC) after elevated temperature was conducted and six temperature levels，room temperature，200 ℃，350 ℃，500 ℃，650 ℃ and 800 ℃were selected to heat the LWAC test blocks． The appearance features of color，crack development and changes on quality were observed after elevated temperature，and the micro-characteristics were analyzed by utilizing the scanning electron microscopy ( SEM) ． The experiment results indicate that，the variation of compressive and tensile strengths of LWAC with the elevated temperature are smoother and slower than those of normal concrete ( NC) ． The residual compressive and tensile strength ratios are obviously larger than those of NC． It provides basic experimental study on the fire resistance of LWAC． If the spalling problem could be well solved at high temperature，the ceramsite LWAC will have potentially better fire resistance than that of NC．