The results of researches on the influence of the terms of harvesting varieties of fiber flax varieties of different ecological and geographical origin on the productivity of fiber and seeds are given. The optimal harvesting dates for the varieties of Zhuravka, Esman and Kamenyar have been established, depending on the target direction of product use. The highest yield of all fiber of fiber flax was obtained in early yellow maturing term depending on the grade of 3.37 t / ha in the Esman variety and 2.58 t / ha in the Kamenyar variety, and the harvesting of these varieties into other phases of ripeness leads to a decrease of 3,1-15,1%. For the Zhuravka variety, the best harvesting period for obtaining the maximum yield of fiber is the phase of green stiffness – 2.78 t / ha).