is a national highway of Japan connecting the capitals of Tokushima and KÃ Âchi prefectures, Tokushima and KÃ Âchi in the island of Shikoku with a total length of .
National Route 55 spans much of the south side of Shikoku traveling southwest from Tokushima to Cape Muroto along the island's coast. At the cape the route changes direction following the coastline still, but to the northwest towards Kà Âchi. and there are almost no steep slopes or curves, so it is also used as a driving course. Most of the road runs parallel to the east branch of the Tosa Kaidà Â, a trade route established during the Yamato period. Near Anan National Route 55 runs along the coast, whereas the east branch of the Tosa Kaidà  runs slightly inland. The scenic view zone along the route is also a typhoon-prone area, and traffic restrictions are often imposed from summer to autumn due to roadside collapses, falling rocks, and high waves. Traffic restrictions may also be put in place when a major tsunami warning is issued. Overall, the highway has a total length of .
On 18 May 1953 Secondary National Route 194 was established along what would become current-National Route 55 between Tokushima and Kà Âchi. It was upgraded to Primary National Route 55 on 1 May 1962. The designation for Secondary National Route 194 was then re-assigned to the current National Route 194 between the cities of Kà Âchi and Saijà Â.