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Relationship between body and facial expression and emotional state of dairy calves The purpose of this research was to identify the existence of facial and body expressions that reflects the emotional state of dairy calves. Thirty-two calves between 1 and 8 weeks of age were studied for four consecutive days. Eight groups with four animals each were formed randomly, forming homogeneous groups among themselves in age. Each group was analyzed twice. The animals were taken to a test chamber with open sides and covered with metal tile over a pasture area, where they received the application of the treatments positive "neck stroking" and negative "umbrella test" (Sandem et al. 2004). The facial expression was analyzed through the facial action units: eyebrow, mouth, nostril and eye white. Body expression was verified by the ear position and tail position variables. The animals were evaluated during six experimental times: natural environment, pre-test, test, post-test 1, post-test 2 and natural environment after the test. Both stimuli caused reduction (p < 0,05) in eye white area from 3,50 cm 2 to 1,10 cm 2 , and area of nostril from 8,58 cm 2 to 6,07 cm 2. The raised eyebrow was present during the negative stimulus. It was not possible to identify if the changes in facial action units were due to positive or negative emotions. All manipulation with the animals caused a change in the facial units. The positioning of ear and tail are related to positive and negative emotions. The "back" ear position and the "arched" tail position are associated with expressing positive emotions. The "horizontal" ear position and the "between hindlimbs" tail position, to negative emotions. The types of ear and tail positions are indicators of positive or negative emotional state in calves, and there is great potential for using these measures to evaluate emotions. Thus, we identified the existence of facial expressions, with the variable eyebrow, and body expression, with the position of "back" ear and "arched" tail that reflects positive emotional states; and "horizontal" ear position and "between hindlimbs" tail reflecting negative emotional states in calves.