The company, known also as JAPEX, said production commenced from the shale formation at a rate of around 220 barrels of oil per day.
"Depending on the results of the demonstration experiment, the amount of production of crude oil and natural gas, which is currently being produced at Fukumezawa oil field, is highly likely to increase," the company said in a statement Monday.
JAPEX said data taken from what it said was a pilot project would be analyzed to determine what steps are needed for a full-scale hydraulic fracturing operation at the site. Based on initial data, the company said it would be ready to move ahead by the end of the year.
Japan's economy started importing more energy products in the wake of the Fukushima nuclear disaster in 2011. The country relies on imports to satisfy nearly all of its energy needs.
Japan in 2012 consumed more than 4.7 million barrels of oil per day, which was the third-largest in the world at the time. It has few proven natural resources of its own.
Total oil production in 2012 was 136,000 bpd, the U.S. Energy Information Administration said.