The current study was conducted to identify the influence of short-term (five days) high stocking density (SD) on broilers' welfare by assessing several thermophysiological parameters in 32 birds of 43 days of age Ross male broiler chickens. Based on broiler's body weight, broilers were randomly allotted into two SD rates; control (26.5 kg/m2) or high (45.0 kg/m2). It appears evident that placing broilers at high SD as 45.0 kg/m2 had manifested noticeable impacts on their thermophysiological responses. This conclusion was demonstrated by the existence of results of the current study showed a major displacements in broilers' homeothermic status, high SD broilers experienced pronounced elevations of their body temperatures as well as head, body and shank surface temperatures over the control SD broilers. Additionally, this was further emphasized by the noticeable displacements of body internal, external and total thermal gradients as well as heat loss index of high SD broilers compared to the control broilers. Based on the presented evidences, short-term high SD markedly increased broilers stress and jeopardize their welfare. Measuring broilers' thermophysiological responses under different rates of SD can be adapted to assess their welfare.