The level of illness acceptance correlates positively with compliance to the doctor's recommendations, and negatively with the frequency and intensity of complications of chronic diseases. The purpose of this study was to determine the influence of the clinical condition on the level of illness acceptance, and to find variables which would have the most profound effect on the level of illness acceptance in patients with chronic respiratory diseases. The study group consisted of 594 adult patients (mean age: 60 ± 15 years) with mixed chronic respiratory diseases, recruited from patients of 136 general practitioners. The average score in the Acceptance of Illness Scale was 26.2 ± 7.6. The low level of illness acceptance was noted in 174 (62.6 %) and high in 46 (16.6 %) patients. Analysis of multiple regressions was used to examine the influence of explanatory variables on the level of illness acceptance. The variables which shaped the level of illness acceptance in our patients included: improvement of health, intensity of symptoms, age, marital status, education level, place of residence, BMI, and the number of chronic diseases. All above mentioned variables should be considered during a design of prevention programs for patients with mixed chronic respiratory diseases.