| Country: | JPN |
| Type: | National |
| Route: | 55 |
| Map Custom: | yes |
| Map Notes: | National Route 55 highlighted in red |
| Length Km: | 210.2 |
| Length Ref: | [1] |
| Established: | 1 May 1962 |
| Direction A: | East |
| Terminus A: | in Tokushima |
| Junction: | |
| Direction B: | West |
| Terminus B: | in Kōchi |
| Previous Type: | Route |
| Previous Route: | 54 |
| Next Type: | Route |
| Next Route: | 56 |
is a national highway of Japan connecting the capitals of Tokushima and Kōchi prefectures, Tokushima and Kōchi in the island of Shikoku with a total length of 210.2km (130.6miles).
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 Kōchi. 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 Kaidō, a trade route established during the Yamato period. Near Anan National Route 55 runs along the coast, whereas the east branch of the Tosa Kaidō 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.[2] Traffic restrictions may also be put in place when a major tsunami warning is issued. Overall, the highway has a total length of 210.2km (130.6miles).[1]
On 18 May 1953 Secondary National Route 194 was established along what would become current-National Route 55 between Tokushima and Kōchi.[3] 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 Kōchi and Saijō.[4]