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Background: the silvopastoral rearing system can be an excellent alternative for pasture milk production, because the system favors a higher production and quality of forage and provides thermal comfort and welfare for the animals, which consequently will lead to better productive performance of the animals. Goal: To evaluate the effect of natural shading on the thermal comfort of dairy cows reared in a silvopastoral system. Methods: we used 16 Girolando cows of low production (7,173.2 kg of milk/day), randomly distributed in two groups±s, each group remained in 6 paddocks, being 3 paddocks with trees (group 1 = G1) and 3 paddocks without trees (group 2 = G2), totaling a period of 90 days, which were divided into 6 periods of 15 days being 8 days of adaptation. During the experimental period, the animals were kept in pasture of Brachiaria brizantha cv. Marandu, supplemented with concentrated feed. The climatological data, temperature (T) and relative humidity (RH) were collected through a meteorological station and the THI - temperature and relative humidity index was calculated from the model defined by Thom (1959), THI = 0.8 x T + [(RH (%) / 100) x (T - 14.4)] + 46.4. With the aid of a thermal camera, the temperature of the pelame of the forehead and nostril was collected, and the respiratory rate (movement/ minute) was counted. With the aid of the R software, analysis of variance was performed at 5 % significance. Results: the THI was 79 ± 2.38 indicating danger and potential thermal discomfort. Therefore, there was no significant difference for the parameters evaluated, the respiratory rate between G1 = 54.91 and G2 59.18 mov/min, p-value = 0.53, standard error = 4.90, frontal temperature in G1 = 43.33 ºC and G2 = 40.12 ºC, p-value = 0.17, standard error = 1.66 and nostril temperature G1 = 40.50 ºC and G2 = 39.63 ºC, p-value = 0.42, standard error = 0.77. Conclusion: the natural shading of the trees did not interfere with the thermal comfort of the dairy cows, however the THI of 79 represents a stress threshold that can cause a drop in milk production yield. [ABSTRACT FROM AUTHOR]