The function of the liver is assessed in patients with maxillofacial phlegmons suffering from endogenic intoxication of different severity. The most marked changes of the enzymatic activity of the liver were observed in patients with progressive phlegmons and complications thereof (mediastinitis or sepsis) involving endotoxicosis of the second or third degree. The authors come to a conclusion on the functional hepatic failure in patients with phlegmons of the face and neck, which fact should be borne in mind when planning combined therapy of this patient population.