A national filariasis survey was conducted to determine the prevalence and distribution of Wuchereria bancrofti microfilaraemia and clinical disease associated with lymphatic filariasis in Ghana. Multi-stage systematic sampling was used to select households to be examined in all 10 administrative regions of the country. The results showed a high prevalence of microfilaraemia and disease with considerable regional variation in all the quantities investigated. In general, the disease was more prevalent in the northern guinea savannah and the southern coastal savannah, while the middle forest belt was relatively free. Even within the regions, there was considerable variation in the distribution of the disease. The disease is of potentially major public health significance, particularly in the northern and coastal savannahs, and requires the design and implementation of a control programme.