Background. Family studies have suggested that eating disorders and mood disorders may coaggregate in families. To study further this question, data from a family interview study of probands with and without major depressive disorder was examined.Method. A bivariate proband predictive logistic regression model was applied to data from a family interview study, conducted in Innsbruck, Austria, of probands with (N=64) and without (N=58) major depressive disorder, together with 330 of their first-degree relatives.Results. The estimated odds ratio (OR) for the familial aggregation of eating disorders (anorexia nervosa, bulimia nervosa and binge-eating disorder) was 7·0 (95% CI 1·4, 28; P=0·006); the OR for the familial aggregation of mood disorders (major depression and bipolar disorder) was 2·2 (0·92, 5·4; P=0·076); and for the familial coaggregation of eating disorders with mood disorders the OR was 2·2 (1·1, 4·6; P=0·035).Conclusions. The familial coaggregation of eating disorders with mood disorders was significant and of the same magnitude as the aggregation of mood disorders alone – suggesting that eating disorders and mood disorders have common familial causal factors.