China has issued new anti-corruption rules which require government workers to report their investments, incomes and assets, state media reports.
Officials must now also give the financial details of family members and any change in their personal status.
Analysts say the new rules are designed to prevent officials from hiding income under the names of other people.
The Chinese president has said fighting corruption is a matter of life and death for the Communist party.
The new regulations, which came into effect on Sunday, are an expansion of laws issued in 2006 and broaden the scope of personal information officials have to declare.
However, the new rules stop short of requiring that the incomes and assets of Chinese officials be made public, the China Daily reported.
Those who fail to comply or submit false information will face "dismissal or discipline", the state-owned newspaper said.
Previously, the harshest penalty was "informed criticism".
The regulations apply to mid-level to senior Communist Party officials and executives at state-owned businesses.
The BBC's Damian Grammaticas in Beijing says that despite a high-profile campaign by the government, corruption among officials remains widespread.
This worries China's leaders, who are seriously concerned that public anger at levels of corruption is undermining support for the Communist Party, he says.