The 30-year-old has yet to fully recover from the Achilles tendon injury that he picked up last month.
He missed Barcelona's 1-1 draw with Mallorca and Spain's two Euro qualifiers against Liechtenstein and Scotland.
"Xavi is getting better and better, so that one side does not have any pain and the other still has a little bit," doctor Ramon Cugat, who treats him, told Spanish TV channel Antena 3.
"He wants to play on Saturday, but I have told him he has to wait a bit because he still has trouble on the other side. It is too early for him to play."
Defending champions Barcelona, who eye a third straight league title, lie fourth in the table with 13 points after six games.
Valencia, who made an impressive start to the season despite selling David Villa and David Silva, are on top with 16 points.