"New technologies and methodologies were used in the media and the government thought it fit and the time is right to make amendments to existing act to accommodate new technologies," minister Rambukwelle said.
Minister Rambukwelle said the law was needed because some websites were publishing 'raw filth'.
The cabinet of ministers and approved the changes. The law would apply retrospectively from January 2012.
Sri Lanka has blocked several websites from being viewed by citizens through local internet service providers.Police arrested several journalists and closed down two websites connected to Sri Lanka's main opposition last month.
Rights activists, media freedom organizations, the US and the European Union have raised concerns over declining media freedoms in the country.