The aim of the study was the comparative analysis of the degree of intensity of male and female hyperthyroidism treated surgically in the years 1990 to 1996. In this period 295 females and 42 males underwent operation for hyperthyroid goitre. Female predominance was noted in hyperthyroidism (ratio 7:1), in Graves' disease (7.4:1) and in toxic nodular goitre (6.3:1). The clinical findings in pre- and postoperative patients, including laboratory, visual diagnosis, and intra- and postoperative complications were evaluated. In the preoperative period, the incidence of the thyreocardiac syndrome was greater in the male. Male hyperthyroidic goitres were more frequently located retrosternally and caused trachea compression. No significant sexual differences were found in routine laboratory tests. Operations for hyperthyroidic male goitres usually caused more intraoperative problems and were connected with greater blood loss. Estimation of cardio-vascular parameters in the early postoperative period showed higher intensification of hyperkinetic circulation and higher mean body temperature in men. Signs of psychosis developed postoperatively in two men. The analysis of patients with hyperthyroidic goitre treated surgically revealed more severe course of male thyreotoxicosis in the perioperative period.