Montella took over from Argentine Diego Simeone, who led the Sicilian side to 13th position and Serie A safety before leaving by mutual consent last week after just four months in charge.
"Catania football club has recruited the services of Vincenzo Montella who has signed a two-year contract," said a statement on the club's website. "The new coach will be officially presented to the press on Friday morning."
Montella, 36, took temporary charge of Roma after Claudio Ranieri's resignation in February but he was not offered an extended contract as the Giallorossi finished sixth and failed to qualify for the Champions League.
Di Carlo returned to Chievo Verona after an unhappy spell with Sampdoria ended with his sacking in February.
The 47-year-old, who had coached the Gialloblu from 2008-10, takes over from Stefano Pioli who led Chievo to 11th last season before being snapped up by Europa League-participants Palermo.
"Domenico Di Carlo will take technical charge of Chievo Verona's first team squad for the 2011/12 season," read a statement on the club's website. "Mister Di Carlo will be formally presented on Friday morning."
Di Carlo's old club Sampdoria, who were relegated to Serie B, appointed Gianluca Atzori as their new coach on a two-year contract on Thursday.
