Purpose: Smoking habit remains to be a major social problem despite new disincentive measures taken recently. In this study, we aimed to evaluate smoking cessation rates of first-degree relatives of patients with smoking related serious pulmonary diseases as well as the change in their point of view about smoking. \nMethods and materials: A questionnaire was administered to first-degree relatives of 68 patients with lung cancer and 30 patients with chronic obstructive pulmonary disease (COPD). \nResults: Average tobacco exposure was 32 pack-years for relatives of lung cancer patients, whereas it was 20 packet-years for relatives of COPD patients (p<0.05). Intention to quit cigarette smoking was present in % 83 of relatives of lung cancer patients and in % 62 of relatives of COPD patients (p<0,01). % 56 of (n=55) total participants declared that they attempted to stop smoking and % 12 (n=12) declared that they tried aided quit attempts. % 51 of the study participants found none of the components of new Tobacco Control Law effective, whereas % 48 found the prohibition of smoking indoor public places effective and deterrent.\nConclusions: Relatives of lung cancer patients have a higher will to quit cigarette smoking. Smoking cessation interventions may be more effective and successive in this group as their motivation is higher as they witnessed tobacco related serious health problems.