There have been conducted comprehensive studies of the effect of UV irradiation on enzymatic activity in the germination period of winter wheat seeds under different irradiation regimes. They have identified the maximum increase in amylase activity on the fourth day from the beginning of seed germination in variants with three and five minute UV irradiation and this indicator’s value exceeded that of the control variant on 58.6 % and 64.1%, respectively. Catalase activity was of its maximum value by the fourth day from the beginning of seed germination in variants with three and five minute UV irradiation and exceeded the value of the control variant on 14.7% and 17.7%, respectively. Peroxidase activity was of its maximum on the eighth day from the beginning of seed germination in all experimental variants. In a variant with three minute UV irradiation, peroxidase activity exceeded the control values of this indicator on 50% and in a variant with five minute UV irradiation on 55%. The use of a mercury-quartz lamp BNPO 2-30-001U3.5 to stimulate physio-logical and biochemical processes in germinating seeds made it possible to identify different enzymatic activities depending on the time exposure to UV irradiation.