The set of measures is in response to Pyongyang's nuclear test in January and long-range rocket launch last month, South Korea's Prime Minister Office said.
Seoul's sanctions include blacklisting 38 North Korean officials and two foreigners, as well as 30 organizations, including 24 based in Pyongyang, that are involved in the North's nuke and missile programs.
The Seoul government said the measure would ban people and organizations from making financial and property transactions with South Korean banks and would freeze their assets as well.
Other punitive action includes prohibiting vessels that have traveled to North Korea in the past 180 days from entering South Korean waters.
The move is aimed at enforcing the toughest-ever UNSC sanctions imposed last week that call for mandatory inspections of all cargo going in and out of North Korea and a ban on the exports of mineral resources, a major source of hard currency for the cash-strapped country, Yonhap News Agency reported.
The government said it will advise its citizens abroad not to visit North Korean restaurants as the communist government operates them to earn hard currency.