The Financial Services Commission (FSC) said local financial institutions should beef up the manpower and investments for computer network security, and chief executives will be held more accountable for cyber system security.
The FSC said it will raise the level of reprimands on people in charge of financial institutions if serious computer security-related problems crop up.
The move came after a series of computer data leaks and hackers' attacks on online financial transactions made it more necessary to beef up local financial firms' computer security.
In March, a hacker broke into the computer system of leading consumer finance firm Hyundai Capital Services Inc. and stole customers' personal data.
In mid-April, the online transaction system of the National Agricultural Cooperative Federation, or Nonghyup, was crippled for almost a week, hit by cyber attacks that North Korean hackers are believed to have waged.
The financial watchdog has set up a task force to examine financial institutions'' computer security and find ways to strengthen it.