The tough winger, who waived his no-trade clause for the move, will provide some much-needed protection for Penguins stars Sidney Crosby, Evgeni Malkin and Jordan Staal.
Laraque has been forced to take a lesser role with the Coyotes this season. He was a healthy scratch for a game against the Flames last week. He expects to be busier in Pittsburgh.
"I won't be the bodyguard of only one guy and I know that," he said. "I'm going to have look after pretty much the entire team."
He's under contract for US$1.1 million this season and $1.3 million next year.
In 56 games this season, he's recorded five goals and 17 assists with 52 penalty minutes.
Carcillo has 21 goals and nine assists in 52 games this season with the AHL's Wilkes-Barre/Scranton Penguins.
Earlier Tuesday, the Penguins acquired veteran forward Gary Roberts from Florida.