Video captured the dramatic scene as the bridge collapsed under the weight of the truck on Friday.
The mostly wooden bridge was built to replace a road bridge destroyed in a previous flood.
But more recent floods had made crossing the wooden bridge risky even before the truck arrived.
The footage showed the truck approaching the bridge and then entering the narrow, rickety structure of the village of Uryum, more than 3,700 miles east of Moscow.
When the truck reached the middle of the bridge, the structure began to fail and it eventually collapsed into the river, taking the vehicle with it.
The driver survived, but his truck was unlucky.
Neither do the residents of Uryum Village – they now have no way to cross the river and will have to build another replacement bridge.
The Uryum Bridge is not the only one to have been damaged by extreme rains in recent days, with flooding also damaging a bridge on the Russian Trans-Siberian Railway.
A bridge has also given way in the Zabaikalsk region, about 190 miles north of the Russian border with China and Mongolia. No casualties were reported.
About 650 houses were flooded and five road bridges were washed away in flooding in the region on Thursday, according to the TASS news agency.
It comes the same week as extreme flooding in China and parts of Europe.