In virtue of experiments was build up heat stress quantitation model.By heat stress (HS) are affected the nigh performance dairy cows ( up 8000 kg milk per lactation). From check method of bodycooling is the most effective n evaporation that reduce to level of heat stress ( by the heat stress quantitation model ) till by 13 % , whole ventilation increasing (air low velocity 2 m.s-1) inside of stable by 5 % only. This body cooling method is effective for lew performance dairy cows ( below 5000 kg milk per lactation ). The evaporation cooling reduce HS in the nigh performance dairy cows during temperatures over 30 degr.C partially only.