  We study the behaviour of the power spectrum (PS) in the case of fractal
structures. We show that in this case the main observational features of the
PS, the large scale flattening and the scaling of the amplitude with sample
depth, are related to finite size effects, due to the fractal nature of galaxy
distribution in the sample. Comparing with the recent results of the PS for the
CfA2 we conclude that this catalog is consistent with the fractal description.
