An image forming apparatus contains a photoconductor having a support and a photoconductive layer disposed thereon. I(S) at the surface of the photoconductor and I(S) at the interface of the photoconductive layer on the support side are 5.010^-3 or less and the sum of I(S)s is 3.010^-3 or more. I(S)s are determined according to following Equations 2 and 3 after subjecting a group of data of N samples of height(t) [m] of a profile curve at the surface or of one at the interface to discrete Fourier transform according to following Equation 1, the N samples being taken at intervals of t [m] in a reference line direction

##EQU1##

wherein n and m are each an integer; N is 2, where is an integer

##EQU2##

##EQU3##