Abstract: The plasma condition and the ga in coef ficient of a carbon fibertarget,which is irradiated by obliqueincident laser light were calculated.　The　refraction of laser and the resonance absorption of Ppolarization laser were considered. The　gain coefficient value of Hlike C,　n=2,3 comparing with verticalincident is higher,however the gain regio n becomes narrower and the gian region towards to the outer layer of the fiber target plasma.