Official media made no mention of the increase, the first in two years, and station operators were at a loss to explain the sudden increase.
Government-run stations doubled their prices for petrol and diesel, while prices for compressed natural gas increased five-fold.
Commuters in Yangon woke up Wednesday to find many of them could not get to work, either because they could not afford the increased bus fares or because buses had simply stopped running due to the higher fuel prices.
"We don't know why this happened," one petrol station operator told AFP.
Myanmar's energy ministry tightly rations fuel, with private cars and taxis each allowed only two gallons (7.6 litres) a day.
Many people fill up their cars every day only to sell the fuel to black market vendors, which is where most drivers actually tank up.
At government stations, petrol prices jumped from 1,500 kyats a gallon to 2,500 kyats (1.
17 to 1.95 dollars). Diesel prices jumped from 1,500 kyats to 3,000 kyats.