Northern Ontario is the part of the province of Ontario, Canada, which lies north of Lake Huron, Georgian Bay, the French River and Lake Nipissing.
Northern Ontario has a land area of 802,000 km² (310,000 mi²) and constitutes 87% of the land area of Ontario, although it contains less than 7% of the population.
In the early 20th century, Northern Ontario was often called "New Ontario", although this name fell into disuse because of its colonial connotations. (In French, however, the region is still referred to as Nouvel Ontario.)
Most of Northern Ontario is situated on the Canadian Shield, a vast rocky plateau. The climate is characterized by extremes of temperature, extremely cold in winter and hot in summer. The principal industries are mining, forestry, and hydroelectricity.