The striker moved to Stamford Bridge in 2007 but struggled to make an impact and spent the 2008/09 season on loan in Germany.
Pizarro helped Werder, who he previously played for between 1999 and 2001, to the Uefa Cup final and impressed when scoring 17 Bundesliga goals.
And the Peru international has now stated that he could remain at the Weserstadion rather than return to Chelsea.
He told BILD: "I am not in touch with anyone from Chelsea Football Club.
"I could imagine staying on as a player of Werder Bremen."
Werder head of board of directors Willi Lemke has revealed the club would welcome the opportunity to keep hold of Pizarro.
"If there is a concrete plan of how to fund the stay of Claudio Pizarro and if this is brought to us by Klaus Allofs (Werder general manager), we would absolutely support an attempt to keep hold of a valuable player," said Lemke.