The interview was carried out with 1664 steelworkers in the aim of obtaining their opinion on subjective fatigue accompanying the work on morning, afternoon and night shifts. Warm and cold seasons of the year were treated separately. Continuous work observations and telemetric heart rate registration were conducted at some workplaces. Analysis of results exhibited a great differentiation of fatigue estimation on particular shifts. Influence of the seasonal factor was found to be very important both in the reported feeling of fatigue as in changes of the pulse rate. Conclusions concern the ergonomic approach to fatigue problems in shift work.