A new automatic air-cooling system is proposed using a cooling incubator to replace the manual water-cooling blanket which has traditionally been used to lower brain tissue temperature (BTT) in brain hypothermia treatment (BHT). This study concerns its feasibility through a simulation. First, a biothermal model is proposed for the adult incubating system based on the geometric structure and parameters of patients. Its dynamics were carefully examined by two simulation experiments testing its step response and feedback control. Then a model reference adaptive control algorithm was introduced for the automatic regulation of BTT, where the newly developed adult incubating biothermal model, represented by a state equation, was replaced for the hypothermic patient with a cooling blanket, thus introducing a first-order lag system given as its basic characteristic model. Finally, the proposed cooling incubator was controlled by the adaptive control mechanism, which gives a follow-up of BTT to a given reference temperature course, even if a possible environmental change in the therapeutic cooling system exists, including the individual differences of patients and any chronic conditional change. The automatic cooling incubating system based on the air-cooling method was confirmed to be superior to the water-cooling one. Thus, this work supports the possible development of an air-cooling adult incubating system for the automatic regulation of BTT in an intensive care unit (ICU) application. © ISAROB 2005.