It means Warburton is free to play again on November 7, but will miss Wales' final RWC2011 clash.
"I am naturally disappointed with the outcome, but now my job is to focus entirely on supporting the boys in their preparations for Friday's match," said Warburton.
Following the hearing today the Welsh Rugby Union Group Chief Executive, Roger Lewis, said: "We are disappointed with the decision to suspend Wales Captain Sam Warburton from the game for three weeks, following his red card dismissal in the Rugby World Cup semi final against France in Auckland.
"The WRU respects the process which has been followed and understands the disciplinary procedures in place.
"Our focus in now totally upon the, forthcoming, third place play-off international, which will be played at Eden Park in Auckland on Friday.
"The WRU further wishes to state its unequivocal support for Sam Warburton as a role model and exemplary captain who has led Wales to formidable success in the competition so far."