Schwarzer joined the Blues last summer on a one-year deal and served as Petr Cech's understudy for most of the campaign.
With the 41-year-old's deal expiring this month, Chelsea have moved to tie down the former Fulham keeper to a new 12-month contract.
Schwarzer made 12 starts and one substitute appearance during his first season at Chelsea, featuring in the UEFA Champions League semi-final against Atletico Madrid after Cech picked up a shoulder injury which ruled him out for the final few weeks of last season.
Meanwhile, Chelsea have confirmed Henrique Hilario has left the club following the end of his contract after eight years in west London.
England defender Ashley Cole and Cameroon striker Samuel Eto'o have also left Chelsea.
"Cole has a very strong claim to be this club's greatest player in his position of all time," Chelsea said in a statement.
"Chelsea Football Club thanks Ashley for the fantastic service he gave throughout his eight years here and for helping to bring so many trophies home. We wish him well for the future."