I Gusti Nyoman Wiratmadja Pudja, director-general of oil and gas at the ministry, said Indonesia will reactivate its membership in November after all OPEC members approved its application to rejoin the oil cartel at a meeting in Vienna last week.
The Southeast Asian country left the group in 2008 after nearly five decades of being the only Asian member amid declining oil reserves and investment. The country joined OPEC two years after it was founded in 1960.
Indonesia hopes membership will strengthen its ability to secure oil supplies and attract investment to its domestic energy industry.
It is Southeast Asia's largest oil producer, but the nation of 250 million people has imported for years because of aging wells and exploration failures. Consumption is continuing to rise but an unpredictable legal system and bureaucracy has deterred foreign investors.
Indonesia with a 2015 oil production target of 825,000 barrels per day would be the fourth-smallest producer in a 13-member OPEC ahead of Libya, Ecuador and Qatar
The government is sending a delegation to oil producing countries in the Middle East and elsewhere, including Russia and Azerbaijan, for possible supply agreements for crude and fuel.