The New York Times said in a lengthy article Friday that most of the alleged wealth was accumulated by Wen's relatives after he rose to high office in 2002.
Hong Kong's South China Morning Post newspaper published a letter Sunday it said was written by two lawyers for Wen's family, Bai Tao and Wang Weidong, saying that The Times' report was untrue. It said family members have not conducted any illegal business activities, do not hold shares in any companies, and that Wen has never been involved in his family's business activities or allowed those activities to influence his policies.
A spokeswoman for The Times, Eileen Murphy, said the newspaper was "standing by our story, which we are incredibly proud of and which is an example of the quality investigative journalism The Times is known for."
In an article Saturday reporting on the lawyers' statement, The Times said its earlier article did not allege any illegal business activity and that there was no evidence that Wen had personally intervened to help family members' investments.
"The article pointed out that as prime minister in a country where the state plays a large role in the economy, Mr. Wen oversaw many government officials whose decisions could play a large role in the fortunes of businesses and investors," it said.
Recent foreign media reports about wealth accumulated by Chinese leaders and their families have added to tensions as China prepares next month for a once-a-decade leadership transfer.
In particular, The Times' report is a blow to Wen's reputation as a politician concerned with bettering the lives of ordinary Chinese.
Chinese authorities have blocked access to The Times' English website and its Chinese-language site that carried a translated version of the story. Searches for the names of Wen, his wife and son on China's popular Twitter-like Sina Weibo microblogging site also were blocked on Sunday.