The ZnO thin film structures were obtained by MOCVD method under atmospheric pressure onto Si substrates heated up to 250-350 оС. The film thickness varied from 0.4 – 0.5 µm. The phase composition, structure and morphology of ZnO films as well as electrophysical properties of ZnO/Si heterojunction on their base were investigated. The possible charge flow mechanisms in ZnO/Si heterojunction are discussed.