Statistics Canada said on Wednesday that the latest figure was also up from a 6.8 per cent gain in April, reports Xinhua news agency.
The acceleration in May was largely due to higher prices for gasoline, which rose 12 per cent compared with -0.7 per cent in April, it added.
According to the agency, excluding gasoline, the CPI rose 6.3 per cent year over year in May, after a 5.8 per cent increase in April.
Price pressures continued to be broad-based, pinching the pocketbooks of Canadians and in some cases affecting their ability to meet day-to-day expenses.
Higher prices for services, such as hotels and restaurants, also contributed to the increase. Food prices and shelter costs remained elevated in May as price growth was unchanged on a year-over-year basis, Statistics Canada said.
On a monthly basis, the CPI rose 1.4 per cent in May, following a 0.6 per cent increase in April.
On a seasonally adjusted monthly basis, the CPI was up 1.1 per cent, the fastest pace since the introduction of the series in 1992.
Wage data from the Labour Force Survey found that average hourly wages rose 3.9 per cent year over year in May, meaning that, on average, prices rose faster than wages in the previous 12 months, said Statistics Canada.