Embryological researches of experimental pollination of walnut (Juglans regia L.) pistillate flowers on different phases of stigma opening reveal that it is receptive to pollination during 6 days. In the frame of dichogamy the most favourable for fertilization morphophysiological state of embryo sac comes in 2-3 days. It is established that Moldavian protandrous varieties, have a shorter receptivity period comparatively to protogynous ones. The most efficient pollinators for establishment of local orchards there are established.