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Sixteen heat stressed lactating cows (8 primiparous and 8 multiparous) were arranged in a replicated 8x8 Latin Square design to evaluate the effect of sprinkling frequency and airflow on respiration rate, body surface temperature and body temperature. Cattle were housed in freestall dairy barns and milked 2x. During testing, cattle were moved to a tie-stall barn for a 2-hour period from either 1-3 pm or 3-5 pm on 8 different days in late August and early September. During the testing period, respiration rates were determined every five minutes by visual evaluation. Skin temperature of three sites was measured with an infrared thermometer and recorded every 5 minutes. Body temperature was continuously recorded every minute throughout the testing period utilizing a data logger and vaginal probe. Treatments were 4 different wetting frequencies with and without supplemental airflow. Wetting frequencies were control (no wetting), every 5 minutes, every 10 or every 15 minutes. Supplemental airflow was either none or 19.8 m3/min. Each wetting cycle provided similar amounts of water for all treatments. Initial data were collected for three initial 5-minute periods prior to the start of the treatments. Average respiration rates were higher (P<0.05) 101.0 vs 72.6 breaths/min for controls as compared to cows treated with wetting cycles every 5 min with supplemental airflow. Cows wetted every 5 minutes with supplemental airflow responded with the fastest (P<0.05) and greater (P<0.05) drop in respiration rate reducing the initial respiration rate by 50% at the end of 90 minutes of treatments. Wetting had a greater (P<0.05) effect on respiration rate than airflow. However, the combination of wetting and airflow had the greatest (P<0.05) effect on respiration rate. When cooling heat stressed dairy cattle, the most effective treatment included continuous supplemental airflow and wetting every 5 minutes.