In 2011-2013, a study on the crossing compatibility and the setting of fruit in distant hybridization within the genus Prunus, among the species P. armeniaca L (apricot), P. salicina Lindl. (Japanese plum), P. cerasifera Ehrh. (myrobalan plum) and the hybrids P. salicina x P. cerasifera was conducted at the Institute of Horticulture in Skierniewice, Poland. The percentage of fruit set depended on the direction of pollination of the crossed species. Most fruits were obtained by crossing P. salicina x P. armeniaca and P. salicina x P. cerasifera. The largest number of fruitlets in relation to the number of pollinated flowers was obtained when two genotypes of P. salicina - Czernuszka and D 17-73, were the maternal parents. The results show that the crossing compatibility and effectiveness in the cross-breeding of the studied species of Prunus are influenced to a greater extent by the genotype of the maternal form of P. salicina than by the genotype of the paternal form of P. armeniaca and P. cerasifera.