Several factors influence sex differences in morbidity and general practice utilization rates. These factors are of a biological, social and behavioural nature and have differential effects on varying morbidity types. Secondary analysis of data from the Australian Morbidity and Treatment Survey 1990-91, was conducted using multiple logistic regression to discriminate female from male patient encounters in general practice. This approach considered possible confounding influences of GP and patient characteristics. The results showed there was a tendency for larger differences in the types of problems managed than in the types of reasons for encounter presented. Morbidity related to the reproductive, genitourinary and neurological systems, the blood, and of a psychological and social nature were significant contributors to female poor health and service utilization. Females were also more likely to present with digestive, cardiovascular and respiratory problems, while males were more likely to have digestive and cardiovascular problems managed. Furthermore, males were more likely to present skin complaints and have them managed. The potentially higher rates for males in cardiovascular, digestive, skin and respiratory morbidity not only reflect biological differences, but suggest differences in health reporting, utilisation and illness preventive attitudes.