The projects include widening the road base of Highway 6, as well as designing new passing lanes and reworking some of the sharper curves in the road.
There will also be more work on smaller highways in the north — 373 and 374.
Premier Greg Selinger says the five-year plan will cost $225 million, and the federal government will be asked to cost-share that amount.
Transportation Minister Steve Ashton says raising the provincial sales tax to eight per cent from seven is a key part of the highway funding.
The sales tax was raised in July, but the law enacting the tax hike was only heading to a final vote in the legislature later Thursday.