The purpose of the study was to evaluate the pulse rate and its behaviour in patients suffering from hyperthyroidism and taking beta-adrenolytic drugs before and after thyroidectomy. Material and methods: The study was carried out on a group of 37 (21 women and 16 men) patients suffering from hyperthyroidism treated with beta-adrenolytic drugs, subject to thyroidectomy, hospitalized at the Department of Surgery “B” in the Regional Hospital in Poznań, in the months of January – December 2005. All examined patients (mean age of women was 36.3; mean age of men was 42.9) received propranolol in doses varying from 5 mg to 20 mg. The evaluation of pulse rate was done on five consecutive days three times a day at given times, by nurse staff using the traditional method of radial artery in wrist region. Results: Pulse rate in patients suffering from hyperthyroidism treated with beta-adrenolytic drugs was already considerably decreased on the third day after the operation. Conclusion: The decreased pulse rate was slightly more visible in patients who, in the pre-operative period, received larger doses of β-adrenolytic drugs and the decrease of pulse rate in the post-operative period was more pronounced in patients not suffering from hypertension.