An organic semiconductor material characterized by having a structure represented by chemical formula 1, the planarity of a main chain A1-X-A2 being disintegrated by steric hindrance between B1 and X and steric hindrance between B2 and X, the organic semiconductor material having a number average molecular weight of about 2,000 to about 200,000: ##STR00001## wherein A1, A2, B1, B2 and X each have a skeleton structure comprising L 6 .pi. electron rings, M 8 .pi. electron rings, N 10 .pi. electron rings, O 12 .pi. electron rings, P 14 .pi. electron rings, Q 16 .pi. electron rings, R 18 .pi. electron rings, S 20 .pi. electron rings, T 22 .pi. electron rings, U 24 .pi. electron rings, and V 26 .pi. electron rings, wherein L, M, N, O, P, Q, R, S, T, U, and V are each an integer of 0 (zero) to 6 and L+M+N+O+P+Q+R+S+T+U+V=1 to 6; and B1 and B2 have an alkyl group.