F1 chief executive Ecclestone this week indicated the oil-rich former Soviet race is taking the place on the calendar formerly occupied by South Korea, where a race at unpopular Yeongam was last held in 2013.
Korean organisers have baulked at the sport's high sanctioning fees.
Speaking this week to F1 business journalist Christian Sylt, Ecclestone said of the country: "I don't want to go back there."
"Baku has been signed," he told the Independent. "It will start in 2015 and will replace Korea.
"They (Korea) did a good job with the track but what they forgot to do was build all the things they wanted to build," said Ecclestone, referring to facilities around the harbourside circuit.
Sylt claims that the Azerbaijan deal was brokered by Flavio Briatore, the ousted former Renault boss and close friend of Ecclestone.
"Briatore put the idea in the mind of the president of the country and that got things going," a source is quoted as saying.