Wal-Mart's move comes less than a month after rival Target Corp said it would exit Canada. Sears Holdings Corp last year lowered its stake in its Canadian operations to about 12%, after failing to find a buyer for its holding in the business.
Sales and margins at both Sears and Target have dwindled in Canada in the face of stiff competition from Wal-Mart.
Wal-Mart said on Wednesday it would spend about $230 million of the planned investment to complete 29 supercentres, including the expansion of several stores to add full grocery departments.
The company is also spending to expand its distribution network and its website, walmart.ca.
Wal-Mart had planed to spend $500 million in Canada in the last fiscal year.
The newly announced supercentres, which are Wal-Mart stores with the addition of full-service supermarkets, will boost its supercentre count in Canada to 309 by the year ending January 2016.