The variation of a parameter of seed production in Pinus sylvestris, the content of sterile seeds in a cone, their percentage of the number of fertile seed buds, was studied in 12 populations of the different forest zones of Ukraine: steppe, forest steppe and forest (Polissya, Rostochya). The highest amount of empty seeds in the cones and their variation were noted for the trees of the steppe and forest steppe zones. Percentage of the sterile seeds in a cone calculated of the number of fertile seedbuds was 15.2 to 1.7 %, with the maximum value characteristic of the steppe zone and the minimum ??? of Polissya. The portion of the cones not containing empty seeds was the least in the population of the southern margin of the range of P. sylvestris .