Objectives. The aim of the present study was to evaluate the effects of demographic characteristics, personality characteristics, dispositional optimism, defensive pessimism, and health-related behaviour components on the number of subjective health complaints among Czech adult respondents between the age of 18 and 93. Subjects and methods. The sample consisted of 703 respondents, 489 (69.6%) female, aged between 18 and 93 years (M = 35.9; SD = 16.3), who completed a large set of self-report measures. The present study summarizes results obtained from the Health Behaviours Scale (Dosedlová, Slováčková, Klimusová, 2013), the Health Complaints Inventory by Osecká, Řehulková, Macek (1998), the Life Orientation Test – Revised, (LOT-R; Scheier, Carver, Bridges, 1994), the Defensive Pessimism Questionnaire (DPQ; Norem, 2002), and the Gordon Personal Profile (GPP-I, Gordon,1953, adapted by Svoboda, 1999). Statistical analysis. In the first step, the authors conducted a Principal Component Analysis with the items of the Health Behaviours Scale. The results were saved as factor scores. In the second step, a hierarchical multiple regression analysis with three sets of predictors was conducted. Results. Personality variables turned out to be the strongest predictors of health complaints: Together with demographic variables, they explained 25.3% of variance in subjective healthrelated ill-being. In comparison, dispositional optimism and defensive pessimism explained 3.7% only while health behaviours explained 7.5% of variance in health complaints. The strongest relations were found to promotion of mental health and to lifestyle regularity. All predictors together explained 36.4% of variance in health complaints. Study limitations. The primary limitation of the study is the use of convenience sample, which may have reduced the degree to which the sample was representative.