The 78-year-old believes that the tournament should not have been awarded to the Gulf nation due to concerns over the climate during the summer months
Qatar beat the likes of USA, South Korea, Japan and Australia to the right to host the tournament, a decision that has been heavily criticised ever since it was confirmed December 2010.
Several high-profile names have voiced their concerns over the high temperatures in Qatar in summer, with a potential winter tournament long earmarked as a necessity to allow the tournament to go ahead, while allegations of bribery emerged within less than a year of Fifa's decision over the 2022 hosts.
Additionally, human rights group Amnesty International has called on Fifa to intervene following a number of reports concerning the treatment of workers in the Gulf nation.
Blatter had previously been adamant that Fifa's decision to grant Qatar the hosting rights was correct, but he has now confessed this is not the case.
"Of course it was a mistake [to award the World Cup to Qatar]," Blatter told RTS.
"But we all know that mistakes are made in life.
"Technical reports from Qatar stated that the temperature in summer is too high to play football. However, this didn't prevent the executive committee from awarding the World Cup to Qatar with a large majority."