Despite earlier reports linking him with Chelsea's city rivals Tottenham, Quaresma sealed a late winter switch to Luiz Felipe Scolari's side.
"Chelsea Football Club is delighted to announce that we have signed Inter Milan winger Ricardo Quaresma on loan until the end of the season," a Chelsea statement read.
Quaresma is tipped to fill-in the gap left by England winger Joe Cole, who was ruled out until the end of the season with a cruciate ligament injury.
The Portuguese international failed to impress since joining the Nerazzurri last summer from Porto for an astronomical transfer fee of around 18 million Euros.
Inter fans seem to have lost their patience with Quaresma, as they jeered the 25-year-old when he was introduced as a substitute in Sunday's 1-1 draw with Torino.
Moreover, head coach Jose Mourinho didn't name the beleaguered winger in his squad for the knock-out stage of the UEFA Champions League.
Now Quaresma reunites with his former coach Scolari, who already has five Portuguese in his roster.