The disclosure comes after last month's Central Information Commission (CIC) order that political parties are public authorities and need to respond to Right to Information queries within six weeks.
Replying to a query filed by RTI activist Subhash Chandra Agarwal, the CPI said that it received Rs.31,362,341 from various sources since 2008.
The total includes contributions made above the amount of Rs.20,000.
"CPI should be complimented to become first and the only political party for disclosing funding made to it by various sources when query was made to the party through an RTI petition," said Agarwal.
He said the CPI disclosed the funding even though it did not approve of CIC verdict bringing political parties under the ambit of the RTI Act.
"Similar RTI petitions were sent to several political parties, including the six which were ordered as public-authorities under RTI Act by CIC through its June 3 order," he said.
The commission in a 54-page order said six national parties - the Congress, Bharatiya Janata Party (BJP), Nationalist Congress Party (NCP), Communist Party of India - Marxist (CPI-M), CPI and the Bahujan Samaj Party (BSP) - have been substantially funded and have the "character of public authority" under the RTI Act.