Photoinduced volume changes in B and P doped a-Si:H films prepared by plasma enhanced chemical vapor deposition (PECVD) method have been studied. It is found that the magnitude of photoinduced volume expansion (DeltaV/V) in doped films is larger (DeltaV/V similar to 6 x 10(-5)) Up to a doping ratio of 0.5 % than that of undoped films of DeltaV/V similar to 10(-6). And, the photo-response of the conductivity degrades with doping ratio. These results cannot be explained by monotonous movements of Fermi level with doping ratio. The origin of the result is proposed to be local structure changes in a-Si: H network by doping.