The aim of the research was to study the reproduc-tive qualities of the sows of large white breeds under crossing with Yorkshire boars. Two groups of sows with 15 heads each according to the principle of analogs taking into account the origin, live weight and age were created for a research. The sows at the age of 12 months with a live weight of 130–140 kg, were covered manually by boars-producers of large white breed and Yorkshire breed. Reproductive qualities of sows of large white breed were assessed by multi-plicity, nest weight at day 21, nest weight at 2 months, number of piglets at 2 months and survival rate of piglets. The complex indicator of reproductive qualities was calculated from the data of the reproductive qualities of sows. In the course of the study, it was revealed that the sows of a large white breed as under pure breeding, so under crossing with boars of the Yorkshire breed have had almost the same indicators by the prolificacy, the number of the piglets at 2 months and survival rate of piglets. However, the sows of the combination (LW × Y) differed from the peers combinations (LW × LW) by the most high indicators of the mass of the nest both at the birth of pigs, and at their weaning in 2 months. Herewith reliable difference between the sows of large white breed combined (LW × Y) and (LW × LW) by mass of the nest under birth piglets was  1,04 kg (P > 0,99), and by mass of the nest at 2 months  7,14 kg (P > 0, 90). Difference by the complex index of reproductive qualities between the sows of a large white breed under different breed combinations: (LW × Y) and (LW × LW) was  3,16 points (P < 0,90), in favor of the combination (LW × Y).