The four-year graduation rate was 76 per cent, up 20 percentage points since 2004.
The Liberal government says it remains committed to reaching an 85 per cent graduation rate.
Premier Kathleen Wynne says an additional 163,000 students have graduated than would have if the government hadn't taken steps to help them complete high school.
This also marks the first year the government is releasing graduation rates for individual school boards across the province, which Wynne says will help parents, teachers and students find areas for improvement.
The premier says helping more students succeed is part of the Liberal government's economic plan for the province.