Abstract: The effect of a new dual-functional flexihilizer KT-30 on the properties of PC were studied. Izod impact strength，melt flow rate, tensile strength，bending strength and cracking time were test by impact tester, melt flow indexer，universal testing machine and electronic balance, respectively.  It  showed  that  with  increasing   KT-30，the  impact  strength  of  PC  increased significantly, the melt flow properties and the flexural and melt flow properties decreased a little, and the stress cracking resistance was enhanced. KT-30 could he finely dispersed in PC matrix and the compounded system could he readily injection molded.  When the mass fraction of KT-30 was 5 %，the impact strength of PC reached 40. 8 kJ/m²，about 5 times that of neat PC.