The Texan was stripped of the seven titles after an investigation by the United States Anti-doping Agency found him guilty of using performance-enhancing drugs.
But the image he shared on the social networking site, below the heading "Back in Austin and just layin' around...", shows him lounging on his sofa below the seven jerseys of his now discredited Tour titles.
The jerseys are hanging in frames on the walls near the L-shaped sofa, each picked out by an individual lightbulb, with a pair of curtains left open to clearly display the last of them.
Last month, the International Cycling Union (UCI) ratified the sanctions recommended by USADA, who concluded Armstrong and his US Postal team ran "the most sophisticated, professionalised and successful doping programme that sport has ever seen".
All Armstrong's results from August 1, 1998 were expunged from the record books, including his seven consecutive Tour de France "wins" from 1999 to 2005, and the 41-year-old was banned for life.
The World Anti-Doping Agency (WADA) also announced last week that it would not appeal against the sanctions, while the International Olympic Committee (IOC) has opened an investigation which could see Armstrong stripped of his road time-trial bronze medal from the 2000 Games.
Armstrong did not cooperate with the USADA investigation and has always denied wrongdoing and though he has since removed the line '7-time Tour de France champion' from his Twitter profile, Sunday's picture is sure to be seen as provocative.
The fall-out from USADA's verdict has been extensive, with 11 of Armstrong's former team-mates receiving six-month bans after admitting their own doping offences in the course of their testimonies against him.
South African mountain-biker David George, who rode with US Postal from 1999 to 2000, was provisionally suspended on Tuesday after testing positive for the banned blood-booster EPO.