The perceived health and stress of seafarers was studied in relation to work stressors and personality characteristics (self concept). The data were collected with a questionnaire. The study group consisted of 591 seafarers representing different occupations of the Finnish merchant fleet. Forty percent of the respondents sailed in ocean traffic, 31% on the Baltic Sea, and 29% in European traffic outside the Baltic Sea. The respondents' age averaged 35 (SD 11) years; 23% were women and 77% men. The amount of perceived stress varied between different occupational groups, the engine crew reporting the most stress. On the average, health status was reported as rather good. Personality characteristics were important explanators of perceived stress and health status. The most important were pessimism-optimism and ego strength. Of the work-related factors, the most important explanatory factors were disturbing noise, climatic conditions on board, occupational group, and received appreciation at work. The quality of interpersonal relations at work did not predict stress or health status. In this study 15-33% of the variance of perceived health status and stress could be explained.