Aim: The purpose of the study was to assess severity of psychological distress in patients suffering from internal illnesses, and to define a correlation between distress and personality traits. Method: 45 patients with leukaemia or lymphoma, 46 with other internal diseases and 45 healthy persons were assessed with the General Health Questionnaire (GHQ-30) and Eysenck Personality Questionnaire (EPQ-R). Results: The GHQ ratings indicate noticeable psychological distress in a half of the patients in both groups (threshold 7/8). About 1/3rd of them were located above the threshold of a psychiatric disorder (12/13). In the control group these percentages were far minor, accordingly 22% and 7%. There were no statistically significant differences in mean scores of neuroticism, extraversion and psychoticism. Controls have a slightly lower mean score of lying than patients. Neuroticism ratings correlated with the GHQ in all the groups (0.51 haematological, 0.58 other internal, 0.48 controls). Other EPQ-R scales did not correlate. Conclusion: About half of inpatients suffered from internal diseases express noticeable psychological distress. Persons with a higher neuroticism score are more predisposed to developing psychological distress under stress caused by somatic illnesses.