The road, and another on Malekula, was funded by a US$50 million loan from China's Exim bank in 2015.
It runs from the island's airport, through the main town Lenakel, as far as Greenpoint, replacing a rough dirt track with a two-lane sealed road.
The Daily Post reports the government is considering a second phase of the project.
Photo caption: The main road through Lenakel, the largest town on the Vanuatu island of Tanna in early 2016. The road has been replaced by a sealed highway, built by a Chinese firm