To evaluate the knowledge and manner of cafe, pub and restaurant (with/without alcohol) workers in our city center about the ban on restriction of indoor smoking. To determine the preparation about the ban, smoking characteristics of workers, the knowledge on passive smoking. A questionnaire was performed to workers. The type of workplace, the number of workers, existence of a restriction of indoor smoking, any preparation about the ban were asked. The job of worker, whether the worker has a knowledge on the ban or not, the idea of the workers on the necessity and practicability of the ban were asked. Smoking history and the knowledge about passive smoking of workers were recorded. Fagerstrom nicotine dependent test (FNDT) was performed to smokers. Eighty four work places with 568 workers included in the study. The questionnaire was performed to 337 workers whose mean age was 29.1/years. 292 of workers were male. 190 of cases were current smokers. 166 of cases (49.3%) know the meaning of passive smoking. Alcohol offering was made at 8 of workplaces. Smoking was forbidden in 20 of workplaces. A preparation was performed about the ban in 30 of (46.9%) other workplaces. 88.4% of workers have knowledge on the ban, 64.7% of them know the punishment of the noncompliance of the ban. 81.3% of the workers believe the necessity and 45.7% of them believe the practicability of the ban. Smokers and especially who's FNBT > 5 have a stronger belief on the necessity and practicability of the ban. We determined that the preparation about the ban was inadequate although there was an little time for the put into practice the law. So we think that the controls of workplaces should be happened frequent.