Yorkshire's Jonny Bairstow, 26, will replace Buttler while England have further strengthened their batting line-up with James Taylor making his first Test appearance in three years.
Buttler, 25, has struggled with the bat in the three-match series, averaging 8.5 runs from four innings.
The final Test begins on Sunday with England 1-0 down in the series.
England fast bowler Mark Wood has been rested for the match to protect a chronic ankle problem.
Captain Alastair Cook will make a call later on whether to play a third spinner or an extra seamer but is not contemplating making any more than two changes.
Cook said Buttler was "desperately disappointed" but took the decision "on the chin".
Bairstow, who will keep wicket in what will be his 20th Test, will move down the batting order to seven with Taylor at five and Moeen Ali continuing as an opener.
Nottinghamshire's Taylor has only played twice for England, his last Test appearance coming against South Africa in 2012.
But he impressed in the one-day series against Australia and averages 47.20 in first class cricket.
Cook said: "Taylor is a far better player now. You don't average 47/8 in first class cricket without being a very good player. He's going to add a lot to our batting in the next few years."
England wicketkeeper Jos Buttler has been dropped for the third Test against Pakistan in Sharjah.