Smoking is currently the most significant risk factor for health according to WHO statements. It has been proven that smoking is the cause of many diseases, for example cardiovascular and respiratory tract diseases as well as impaired fertility and decreased immunity. The adverse effects of cigarette smoking on pregnancy and health of children were also proved. However, special attention is laid on impact of smoking on the development of cancer. In tobacco smoke there are over 4,000 different chemical substances and compounds, of which more than 50 are carcinogens. The present study was aimed to assess the knowledge of students and employees of Collegium Medicum of Nicolaus Copernicus University in Torun (CM UMK), first on number and types of carcinogens contained in tobacco smoke and secondly on types of diseases caused by smoking. There were 480 responders included to the study(253 women and 227 men). Among them there were 416 students of CM UMK, 59 students of biomedical engineering at the University of Technology and Life Sciences in Bydgoszcz and 5 employees of CM UMK. Among the respondents there was considerable ignorance about the number of carcinogens contained in tobacco smoke with over 50% of them indicating the incorrect answer. Among the carcinogens there were mentioned mostly tar and nicotine, and among the diseases caused by tobacco smoke most often pointed response there were lung and larynx cancer and heart and blood vessels diseases and to reduce the weight of newborns. In summary, we can conclude that the awareness of students and employees of CM UMK about the carcinogenic properties of tobacco smoke was not sufficient. Respondents were aware of the dangers of smoking, they knew the basic carcinogenic substances and pointed a few diseases caused by smoking cigarettes. Unfortunately their knowledge does not refer to a number of diseases which in common believe are not connected to cigarette smoking, but in fact tobacco smoke is very important for their development.