After joining Chelsea in a £10.3 million transfer from Barcelona last September, the 34-year-old scored just three goals in 22 games.
Chelsea's pre-season trip to the United States did not feature the Gabonese international.
Kai Havertz and Mason Mount are two players who have already departed Chelsea during the summer transfer window.
Havertz of Germany has joined Arsenal, while Mount of England has left for Manchester United.
Aubameyang has had a terrible season at Chelsea and will leave with a year left on his contract.
The 34-year-old was brought in by Thomas Tuchel, with whom he previously worked at Borussia Dortmund, but Tuchel was fired shortly after his arrival.
Graham Potter, Tuchel's replacement, did not select Aubameyang in his Champions League roster and frequently chose Havertz in the forward's role.
Aubameyang did play under Frank Lampard after Potter was fired in April, but he struggled to make an impression.
Chelsea, who are currently coached by Mauricio Pochettino, have also left out Romelu Lukaku, Hakim Ziyech, and Callum Odson-Odoi for the pre-season tour.">