There was a need to develop accurate and effective methods for assessing pain in birds in general and in chickens in particular, as chicks are laboratory animals that are easily raised and dealt with, as well as having neurological components to interact and respond to pain the same as in mammals. Birds have physiological and/or behavioral signs of pain. The physiological signs of pain include the change in heart rate, respiratory rate, and blood pressure, and the flapping of the wing. The behavioral signs of pain that extend from the withdrawal response, calling, and the flapping of the wing. This article focused on the methods of pain assessment in birds in the published literature that varying according to the type of stimulus. However, this review offers information on pain assessment approaches and associated behavior, which can enhance specialists' Understanding of the pain causes and, thus, we can evaluate the analgesic drugs for pain in chicks.