But Armstrong, 41, likely will not offer great detail about specific cases and events, the paper said, citing an unidentified source with knowledge of the situation.
The interview is scheduled to tape on Monday (local time) at Armstrong's home in Austin, Texas, and set to air on Thursday on the Oprah Winfrey Network.
Such an admission would mark a major reversal for the famed cyclist. Armstrong has always vehemently denied using performance-enhancing drugs and has never been proven to have tested positive.
But an October report from the US anti-doping body USADA cited Armstrong's involvement in what it characterized as the "most sophisticated, professionalized and successful doping programme that sport has ever seen," involving anabolic steroids, human growth hormone, blood transfusions and other doping.
Less than two weeks later, Armstrong's seven Tour de France victories were nullified and he was banned from cycling for life after the International Cycling Union ratified the USADA's sanctions against him.
The New York Times reported last week that Armstrong was considering an admission of using banned drugs with the hopes of persuading anti-doping officials to allow him to resume competition in athletic events that adhere to the World Anti-Doping Code.
Another motivation might be to keep the scandal from hurting Livestrong, the cancer-support charity he founded in 1997, USA Today said on Saturday. Armstrong, a survivor of testicular cancer, stepped down as a board member in November.
Armstrong's planned admission, however, carries the risk of getting him sued or held reliable by those who believe he defrauded them by lying about his use of drugs, the paper reported.
