| Country: | JPN |
| Type: | National |
| Route: | 409 |
| Map Custom: | yes |
| Length Km: | 119.3 |
| Length Ref: | [1] |
| Established: | 1 April 1982 |
| Direction A: | West |
| Terminus A: | in Takatsu-ku, Kawasaki |
| Junction: | |
| Direction B: | East |
| Terminus B: | in Narita, Chiba |
| Previous Type: | Route |
| Previous Route: | 408 |
| Next Type: | Route |
| Next Route: | 410 |
National Route 409 is a national highway of Japan connecting Takatsu-ku, Kawasaki and Narita, Chiba in Japan, with a total length of 119.3 km (74.13 mi).