ABSTRACT The objective of this study was to evaluate the effect of chamomile extract on Japanese quail on their performance, animal behavior, tonic immobility, body injuries, and surface temperature. The trial was conducted using 108 quail distributed in a completely randomized experimental design, with three treatments (0, 2.5, and 5.0 g chamomile/kg of feed), six replicates, and six birds per treatment, evaluated in six measures repeated in time (14, 28, 42, 56, 70, and 84 days of trial). The inclusion of chamomile presented a quadratic effect on sitting behavior, estimating the inclusion of 1.8 g chamomile/kg to maximize this behavior. There was a decreasing linear effect for aggressive pecking, that is, the higher the inclusion of chamomile in the diet, the lower the expression of this behavior. The inclusion of 1.8-5.0 g chamomile/kg in a Japanese quail diet reduces the behavior of aggressive pecking, in addition to keeping the birds seated longer. These results are innovative because they show in the literature for the first time that chamomile supplemented in Japanese quail diets has the capacity to modulate the behavior of the quail, leading to an improvement in the welfare of quail raised in cages.