The article discusses the effect of microwave radiation on the seeds of Scots pine (Pinus sylvestris L.). The aim of the research is to increase the efficiency of pre-sowing treatment of seeds with Ultra-high-frequency radiation (UHF) radiation, allowing one to increase the standard planting material yield and reduce its cultivation time. The specificity of enzyme systems for stressing effects is revealed, the dynamics of their change in the period after irradiation is ambiguous and depends on the time of irradiation. The stimulating and lethal doses of radiation are determined. The results show seed treatment with stimulating doses causes reversible changes in the structure and function of enzymes. The regularities and model of the impact of UHF radiation as a stimulating factor on seed viability are established. When exposed to stress factors (radiation), an increase in the activity of enzymes is observed, leading to the excitation or inhibition of growth processes at the first stages of development. As a result, a stimulating effect arises – the germination of seeds increases, the growth of seedlings in height increases, or depressing – the germination decreases and the growth of seedlings slows down.