臼井橋, Steel girder bridge in Niigata, Japan

The Usui Bridge carries National Route 460's Usui Bypass across the Shinano River between Konariba in Akiha Ward and Usui in Minami Ward, Niigata. Opened in 2015, it is 514.6 m long: an eight-span continuous steel plate girder section of 8×40.15 m plus a three-span continuous steel box girder section of 60.3 + 70.0 + 60.3 m, with a total steel weight of 1,746 t.

The first Usui Bridge, a wooden structure, was completed in January 1927 and was the only wooden road bridge over the Shinano River in the Shirone area to survive the June 16, 1964 Niigata earthquake. A second bridge, 383.6 m long and 8.8 m wide, replaced it on August 30, 1971. The third bridge opened on October 12, 2015, completing the Usui Bypass of National Route 460.

The bridge's name comes from Usui, the left-bank district in Minami ward, while the right bank is Konariba in Akiha ward. Before the third bridge opened in 2015, Niigata Kotsu buses stopped at both ends and passengers walked across the old bridge to continue their journey.

The current bridge, opened on 12 October 2015, carries National Route 460's Usui Bypass between Konariba in Akiha Ward and Usui in Minami Ward. The second bridge, finished in 1971, was closed to traffic when the new span opened, so cross via the bypass alignment. The Ogo Bridge on Niigata Prefectural Route 46 lies downstream and the Kosudo Bridge on Route 41 upstream.

The first bridge, a wooden structure finished in January 1927, was the only wooden road bridge over the Shinano in the then-Shirone area to survive the June 16, 1964 Niigata earthquake. By then it was badly deteriorated, and Niigata Kotsu buses stopped at both ends so passengers had to walk across.