OBJECTIVE The aim of the present study was to examine whether psychiatric morbidity can influence the type of illness behaviour of neurological inpatients. METHODS For this purpose, we compared neurological inpatients with and without psychiatric disorders (DSM-IIIR criteria) for the seven scales of Illness Behaviour Questionnaire (IBQ) and searched for possible differences between the two patient subgroups. RESULTS Of the 105 neurological inpatients who participated in the study, 54 (51.4%) were diagnosed as having some type of psychiatric disorder. These patients scored significantly higher than patients without psychiatric morbidity in the scale of Irritability. A suggestive trend for higher scores in the scales of Hypochondriasis, Disease Conviction, and Affective Disturbance, and significantly lower score in the scale of Denial, in patients with psychiatric morbidity, were also found. CONCLUSIONS The present study has shown that neurological inpatients with psychiatric morbidity tend to develop more intense illness behaviour than those without. The effect of psychiatric morbidity on certain components of illness behaviour in neurological patients can be taken into account when therapeutic strategies are planned.