The Bosnia and Herzegovina international midfielder has just over 12 months left on his current deal at the Stadio Olimpico, which has led to speculation that he could be sold this summer.
European heavyweights Bayern Munich, Paris Saint-Germain, Monaco and Manchester United are all rumoured to be courting the 24-year-old's services.
"Fans can be calm," he told Gazzetta dello Sport.
"My contract runs until 2015 and although I know that many big clubs are interested in me, I'm totally focused on Roma and everybody knows that.
"I talked with Rudi Garcia [coach] about all that and he knows that I'm only concentrated on my work."
Pjanic also insisted that he has not ruled out a new deal with Roma.
"A new contract with Roma?" he added. "A contract extension will come by itself. Many times I have said that I'm very happy at Roma."