The 1978 National League was contested in 1978 as the second division of Speedway in the United Kingdom. Newport Dragons dropped out of the league after just one season of second tier racing, however two new entrants - Milton Keynes Knights and Barrow Furness Flyers - saw the league expanded to twenty teams. Weymouth changed their nickname from Wizards to Wildcats. Canterbury Crusaders won the National League title. Although equal on points with Newcastle Diamonds they won by virtue of the fact that their race points difference was greater than their rival.