Abstract: In order to determine the effects of compressive preload on impact damage performance of composite laminates, low-velocity impact and quasi-static indentation tests were carried out on carbon fiber/bismaleimide resin CCF300/5428 laminates under different compressive preloads firstly. Then, delamination area and residual strength of the laminates were obtained by thermally deplying and compression after impact tests respectively. The results show that compressive preload will reduce the contact stiffness and bending stiffness of the laminates significantly, which causes the increases in dent depth and crack length of back matrix for the laminates under the same impact energy. For the quasi-static indentation process and impact processes under the same impact energy, both of delamination initiation load and peak load decrease with the increase of the compressive preload. Under the same impact energy, total delamination area in the laminates and absorbed impact energy ratio increase continually with the increase of compressive preload, leads to the continuous reduction in residual compressive strength. In conclusion, compressive preload will reduce the impact damage resistance of composite laminates and is unfavorable to the damage tolerance performance, which means that it is necessary to take the effects of compressive preload on impact damage performance into consideration during the test verification process of the structures under compressive load.