National Route 280 is a national highway of Japan that traverses the prefectures, Aomori and Hokkaido as well as the Tsugaru Strait that separates them. It currently is made up of two sections that travel 150.7 kilometres (93.6 mi) from Aomori, north across the Tsugaru Peninsula to Sotogahama where the first section ends at the site of a former ferry to across the Tsugaru Strait to the town, Fukushima. The other section begins at the corresponding former ferry terminal in Fukushima. The road then travels alongside the southern coast of Hokkaido concurrently with National Route 228 to Hakodate where the route meets its northern terminus.

Japan has a nationwide system of national highways distinct from the expressways. The Ministry of Land, Infrastructure, Transport and Tourism and other government agencies administer the national highways. Beginning in 1952, Japan classified these as Class 1 or Class 2. Class 1 highways had one- or two-digit numbers, while Class 2 highways had three-digit numbers. For example, routes 1 and 57 were Class 1 highways while 507 was a Class 2 highway.