The Portuguese international was ruled out of the match in two weeks after being booked in the first half of Wednesday's 1-0 win at Tottenham Hotspur.
However, the good news for Real is that defender Pepe will be available against Barca after being banned for the game at Tottenham.
With Real already 4-0 up from last week's first leg against Spurs, coach Jose Mourinho substituted two of his players in the second half at White Hart Lane to avoid the duo possibly suffering the same fate as Carvalho.
"As time passed Spurs became less of a threat, we got hold of the ball more and managed to control the game more," said Mourinho.
"As a result I was able to take off two of the players already on yellow cards - Sergio Ramos and Cristiano Ronaldo," the coach told reporters after his side romped to a 5-0 aggregate victory.
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