DNA found on the clothes of a New York hotel media reports have claimed.
The unconfirmed reports cited sources close to the investigation.maid who accused Dominique Strauss-Kahn of sexually assaulting her matches that of the former IMF chief, US
More tests from the room where the alleged attack took place are pending.
Mr Strauss-Kahn denies the charges, and resigned as head of the International Monetary Fund last week to defend himself.
He is under house arrest in a New York apartment, after a judge granted him a $1m (£620,000) bail last week.
Reports about the DNA samples came after authorities analysed the work clothes of the 32-year-old hotel maid who says she was assaulted in the New York Sofitel near Times Square on 14 May.
Police and judicial spokespeople have declined to confirm the reports, carried by the Associated Press and ABC News, among others.
Investigators are reported to be carrying out further tests on samples taken from the carpet and other surfaces in the hotel room.
Mr Strauss-Kahn is charged with seven counts including four felony charges – two of criminal sexual acts, one of attempted rape and one of sexual abuse – plus three misdemeanour offences, including unlawful imprisonment.
His accuser, an immigrant from the West African state of Guinea, told authorities that Mr Strauss-Kahn had accosted her after she entered his hotel room to clean it.
Mr Strauss-Kahn’s defence team is expected to argue that a sexual encounter occurred, but that it was consensual.
“The forensic evidence, we believe, will not be consistent with a forcible encounter,” Mr Strauss-Kahn’s lawyer, Benjamin Brafman, has said.
Mr Strauss-Kahn, 62, is due to enter a formal plea on 6 June.
He was seen as a leading candidate to be the next centre-left French presidential candidate until news of the accusations broke.
In France, the newspaper Le Monde reports that “people close” to President Nicolas Sarkozy knew more about the private life of Mr Strauss-Kahn than was publicly known.
The newspaper said those closest to Nicolas Sarkozy were touting information, leaked from a police report, that suggested Mr Strauss Kahn had been caught kerb-crawling in a known red light district in Paris.