A model of extracorporeal biological perfusion of the isolated thyroid gland in dogs has been developed. The experiments on dogs were performed to analyse the functional state of the perfused gland. It has been shown that the functional state parameters in 6-hour perfusion were comparable to the control values. It is concluded that the model suggested creates physiologic conditions and can be employed as a model for studying the influence of various factors on the isolated thyroid gland, as well as for investigating problems related to thyroid gland transplantation.