"It seems to me that at certain times and in certain places Lance is not being treated with any respect," Contador, a double Tour champion who returned from a two-year doping ban in August, told reporters in Paris at the presentation of the 2013 edition of the race.
"He is being humiliated and lynched, in my opinion. He is being destroyed," the Saxo Bank-Tinkoff rider, who had a difficult relationship with Armstrong when they were team mates at Astana, was quoted as saying by Spanish media.
"Right now people are talking about Lance but there has not been any new test or anything," Contador added. "It's based exclusively on witness statements that could have existed in 2005.
"I respect each rider's decision but I would have liked it to happen a bit earlier."
Armstrong was stripped of his 1999-2005 Tour victories on Monday when the International Cycling Union (UCI) ratified the U.S. Anti-Doping Agency's decision to erase his results from August, 1998 .
Armstrong, who fought back from cancer to dominate the sport, has always denied doping and says he has never failed a drugs test.
"What there is (in terms of evidence) I don't know, what I do know is that if cycling is popular in the United States it's thanks to him," Contador said.
"If they know over there what the Tour is it's thanks to him, if there are top-level teams and races in his country it's thanks to him."