A large majority (145) of the 217 lawmakers approved the bill, encouraging, in article 17, whistleblowers and civil servants to come forward.
The law also promises reward to anyone whose action may lead to identify authors of corruption or may help recover lost money.
Parliament speaker Mohamed Ennaceur said the adoption of this law is an important step in the fight against corruption, state-run news agency TAP reports.
The parliament is yet to adopt a bill on illicit enrichment and fight against conflict of interests.
Corruption according to experts has had heavy negative consequence on the country’s economy, inflicting a downward trend to growth.
At least 450 million dinars (€200 million /$230 million) in bribes were slipped to state employees in 2013 alone, says the Tunisian Association for Public Auditors.
The phenomenon was one of the key factors which brought down former autocratic ruler Ben Ali in 2011.