The pair were the only two rendered unavailable for Barca's UEFA Champions League clash at APOEL Nicosia on Tuesday.
Iniesta, 30, picked up a calf strain in the El Clasico against Real Madrid in October, and remains out of contention for Luis Enrique's side.
Belgian defender Vermaelen, meanwhile, has battled hamstring, knee and calf problems already in 2014, and the former Arsenal man's woes continued on Sunday as Barca revealed another hamstring injury.
Vermaelen has not featured at club level since coming on late in Arsenal's 1-0 win over West Brom in the Premier League in May.
"That means no places for Andres Iniesta, who has yet to be declared fully fit, or for Thomas Vermaelen," a club statement read, after Barca named a 22-man squad.
"The Club Medical Services have said that the player [Vermaelen] has a right hamstring injury."
Barca are already assured of their last-16 spot in Europe with two games to play, but remain one point behind Group F leaders PSG.
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