The former NBC executive, who was responsible for acting as a liaison between Twitter and news organizations, will be handing over the reins to Adam Sharp, who leads the government and elections team, a Twitter spokeswoman told Reuters.
In her parting tweets, Schiller said her departure would allow Twitter vice president of Global Media Katie Stanton to "reorganize" as she saw fit.
Stanton, formerly head of international strategy, filled in for Chloe Sladden, who left the online messaging service as part of a recent management shake-up that also included the departure of former chief operating officer Ali Rowghani.
Schiller, who joined Twitter alongside Rowghani and Sladden, becomes the latest executive to depart as the company reshapes its executive ranks.
Stanton, who also is on the board of French conglomerate Vivendi SA, became Twitter's new media chief in July, placing the former Google Inc executive at the heart of crucial relationships with Hollywood and the global media industry.
On Wednesday, Schiller credited both former executives for convincing her to join.
Twitter, which has battled to reverse a steady decline in its once-heady pace of growth, surpassed targets for virtually every metric Wall Street scrutinized in its last reported quarter.
Prior to this result, Twitter had lost a large chunk of its market value since the start of 2014 - at the back of lackluster user and usage growth.
© Thomson Reuters 2014