The Catalan club hope to recoup £21million for the 33-year-old despite signing him on a free transfer in January.
Chelsea are in the market for attacking reinforcements following the departures of Romelu Lukaku and Timo Werner this summer and view the former Arsenal man as an option.
According to journalist Toni Juanmarti, They have now had a £12m bid rejected but it remains to be seen whether Chelsea would be willing to pay the fee wanted for a player in the latter stages of his career and who would command a large salary.
Blues boss Thomas Tuchel managed Aubameyang during their time together at Borussia Dortmund and has fond memories of their time at the Bundesliga club.
"I enjoyed working with him [Aubameyang] a lot, it was a pleasure. I've never had any issue," said Tuchel when asked about his relationship with the Gabon international.
"Some players stay your players because you work very, very close, Auba is one of these players. We had a very close relationship.
"Always when we played him here with Arsenal, there was always straight away this close bond. They always stay your players in a way, Auba is one of these guys."
Tuchel's words have done little to quash rumours of a swoop for Aubameyang and with the transfer window entering its closing weeks and Barcelona keen on a sale, the striker could soon be making a premature move back to London.
Aubameyang had his contract terminated in January by mutual agreement so that he could push forward a move to Barcelona.
His north London exit was in part due to a number of disciplinary issues which led to him losing the Arsenal captaincy.
Aubameyang scored 11 goals in 17 La Liga games, helping thrust Xavi's men up the table to an eventual second-placed finish and qualification for next season's Champions League.
But the recent signing of Robert Lewandowski has seen him banished to the substitutes bench and was introduced in the 82nd minute of Saturday's goalless draw at home to Rayo Vallecano.