The modern sheep breeding industry is predominantly based on the efficient meat and milk production. At the same time, the woolen productivity is one of the strategic components of a country's raw material security in the production of various products from it, where the Romanivska breed occupies an appropriate place. Results of research of indicators of woollen productivity of sheeps of Romanivska breed of different sex-age groups (adult ewes of 2-3 lambing times, ewe lambs and cowslip at birth, at 2-, 4-and 6 months of age) are given as a result of interaction of hereditary information and paratypical factors. The formation of physical and technical properties of sheep wool, age variability of its growth and development were studied depending on the season and technological use. Wool productivity has been evaluated by individual accounting for the wool shear of the entire test livestock up to 0.1 kg. During the shearing, the wool shear of the unwashed wool and the output of the washed fibre were determined. The natural length of the wool set with precision to 0.5 cm using a millimeter ruler; true length-on the device FM-0.4; the fineness of wool fibres-using the microscope «MP-3». A pronounced differentiation of the wool fibres by the fineness was established. The morphological composition of fleece wool can be a breeding trait closely related to the type of constitution of sheep, and directly affect the technological properties of wool raw materials. Thoroughbreed belonging of sheeps, age, sex, feeding and keeping of animals, selection and choice by level of woolliness have a significant influence on the formation of wool. The most intensive growth of wool in length occurs during the first two months of postnatal development of animals.