The stimulus package will include an extra 6tn Korean won ($4.94bn; Â£3.42bn) in public spending.
It will also include an extension of existing tax cuts on cars.
Overall, the package will see an additional 21tn won of spending in the first quarter, the Yonhap news agency said.
South Korea, Asia's fourth largest economy, has been hit by slowing global growth, falling oil prices, and softer demand out of China, one of its most important trading partners.
The latest stimulus measures, which will also see cheaper loans made available to some local companies, are designed to help boost exports and domestic demand.
Disappointing trade numbers released on Monday showed exports contracted 18.5% in January from a year earlier.
It marked the 13th month in a row the nation's exports had fallen and was the worst result for exports since mid 2009.
South Korea's annual inflation rate also cooled to its lowest in four months in January.
Official numbers released in January showed the economy expanded in 2015 at its slowest pace in three years - growing 2.6% from a year earlier. The central bank has now revised down its forecast for growth in 2016 from 3.2% to 3.0%.
Further still, South Korea is facing high levels of youth unemployment.
"The government will mobilise all available means and resources in order to boost domestic consumption and exports in the first quarter to March and to help create new jobs," Yonhap quoted the ministry as saying.
South Korea's economy was in part held back last year by the effects of the deadly Mers virus which affected tourism and domestic spending in the first half of the year.

GRA president Dermot O'Brien told Irish broadcaster RTÉ that the force's unarmed status was envied but he added that society was becoming more dangerous.
Ahead of the GRA annual conference on Monday, Mr O'Brien said officers needed an "intermediate form of force" such as a stun gun.
He also said they were angry about pay.
The GRA president said his members had taken a 25% pay cut since 2009 and he called for their salaries to be restored by the next government.
The GRA is the largest professional body to represent members of An Garda Síochána (Irish police force) and campaigns for better pay and working conditions.
Its membership currently stands at about 10,500 officers.

Following an inspection, the officials decided that areas of the playing surface were unsafe.
No new date has yet been set for the game to be played.

The inmates stole five rifles; a guard and an inmate were killed in an exchange of fire.
The authorities have begun a manhunt for the fugitives with the help of UN peacekeepers stationed in the country.
The Haitian government tweeted that it condemned what it described as a prison mutiny.
"One guard was killed during the incident," Justice Minister Camille Edouard Junior told Reuters news agency.
"Three prisoner were wounded, including one who died as a consequence of his wounds."
Eleven escapees have so far been detained, and checkpoints have been set up on roads near the prison.
However, inmates at Arcahaie do not wear prison uniforms, making it easier for them to blend in with the general population.
Haitian prisons are notoriously overcrowded and inmates spend years in pre-trial detention.
South Korea's government has unveiled new stimulus measures following a raft of disappointing economic data for the export-dependent nation.
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Irish police officers should be issued with stun guns, according to the Garda Representative Association (GRA), which represents rank and file officers.
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Saturday's National League game between Dagenham & Redbridge and Bromley has been postponed because of a frozen pitch.
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More than 170 inmates have escaped from a Haitian prison in Arcahaie, 45km (30 miles) north of the capital Port-au-Prince.