The right to clean air in public places (RCA) is a useful indicator of health consciousness. We surveyed the life style and consciousness towards RCA among employees working at the head office of a major company in Osaka, and examined the relationship between life style and knowledge aspect of RCA, one of the three aspects of consciousness towards RCA. Knowledge on laws concerning smoking regulations in public places was classified into two categories. One was knowledge on laws concerning general matters and the other was knowledge on laws concerning concrete and specific matters. Therefore, there are two kinds of relationship; the relationship between life style and knowledge on laws concerning general matters and the relationship between life style and knowledge on laws concerning concrete matters. These two relationships were examined with statistical procedures. Mean scores of knowledge on laws of subgroups divided by HPI score (POOR, MODERATE and GOOD) within groups divided by age and sex ("M. smoker," "M. nonsmoker" and "F. nonsmoker") were compared by t-test. Life style related to knowledge score was checked by correlation coefficient. The following results were obtained. (1) Relationship between life style and knowledge on laws concerning general matters Knowledge scores and their age-adjusted scores of MODERATE groups were the lowest among the 3 groups ("M. smoker," "M. nonsmoker," "F. nonsmoker"). This set of questions was designed to measure the knowledge level on laws concerning general matters. One would have abundant knowledge if one is health-conscious. In other words, those who do many things beneficial to physical health and have a high HPI have a wealth of knowledge on laws concerning smoking regulations on general matters. In the case of the employees, MODERATE groups were less health-oriented than others ("POOR," "GOOD") within the 3 groups ("M. smoker," "M. nonsmoker," "F. nonsmoker"). (2) Relationship between life style and knowledge on laws concerning concrete matters This set of questions was designed to measure the knowledge on laws concerning concrete and specific matters. To attain high scores, it is necessary to have more smoking experiences in various types of indoor places. POOR group of "M. smoker" and MODERATE groups of "M. nonsmoker" and "F. nonsmoker" had high knowledge scores. They were considered to have greater opportunities to visit public places where smoking is permitted (for example, bars) irrespective of their smoking status.