Up to a few years ago, cluster headache (CH) was not thought to be an inherited disorder. However, several recent studies have suggested that genetic factors play a role in the disease. Genetic epidemiological surveys have shown that first-degree relatives of CH patients are more likely to have CH than the general population. CH has been reported in some concordant monozygotic twin pairs. At present, the type and the number of genes involved in the disease are still unclear. No mutation in the CACNA1A and NOS genes was found in CH patients. Recently, we have reported a significant association between the HCRTR2 gene and the disease. The purpose of this review is to describe recent advances in the genetics of CH.