"This is going to be my last series, I have decided to quit," he told reporters in Bangalore on Thursday.
"I have told my team mates before coming here that this four-Test series would be my last. I thank everyone for the support they have given me. I hope I will end my career on a winning note," the former India captain added.
Ganguly was a surprise inclusion in the squad for the Australia series after being left out of the Rest of India team for the Irani Trophy match against Delhi[Images].
"Honestly, I didn't expect to be picked for this series," said the left-hand batsman, who aggregated less than 100 runs in the recent series against Sri Lanka[Images].
The 36-year-old Bengal stalwart, who staged a spectacular entry into Tests with a debut ton at Lord's in 1996, made a storming return to the five-day game in South Africa[Images]in late 2006 after losing his place earlier that year.
He amassed over 1100 runs, with 239 his career-best score against Pakistan in Bangalore in late 2007, at a fantastic average of 61.44 last year, which compares very favourably with his career average of 41.74 in 109 Tests.
He was unable to maintain that high in the current year, though he came up with important knocks, like the 87 against the visiting South Africans at Kanpur, that helped India level the three-Test rubber in April.
This, however, was followed by his poor run in Sri Lanka, where his best score was 35 in six innings.
Ganguly is among the few Indians who have played over 100 Tests but has a poor record against Australia, especially at home, where he averages only 27.35 in nine matches, with a best innings of 66