Two drivers escaped injury after a B-Double truck rolled over on the Hume Highway south of Goulburn this morning.

The crash happened about 3.30am, one kilometre east of Cullerin Road near Breadalbane.

The male truck driver was uninjured in the crash which has blocked both lanes of the highway.

A second crash occurred when a white car was unable to avoid the wreckage of the truck. The female driver of that car was not hurt.

All southbound vehicles have been diverted onto the Federal and Barton Highways, rejoining the Hume Highway at Yass.