"This will be my last series," Ganguly, 36, told reporters after a training session ahead of the first Test starting in Bangalore on Thursday.
"Before coming here, I spoke to my team-mates and hopefully I will go out with a winning knock."
Ganguly was a surprise inclusion for the first two Tests after being ignored for the five-day domestic Irani Cup tie last month, regarded as a trial match for the series.
There was media speculation that the Board of Control for Cricket in India (BCCI) had struck a deal with Ganguly to give him a graceful exit, provided he agreed to quit after the series.
Ganguly denied the charge, but admitted he was disapointed at being left out for the Irani Cup, and surprised when the selectors picked him for the Tests.
"The speculation about my future has been going on for a long time, but I categorically deny any talk of a 'voluntary retirement scheme', which is what the media is calling it," he said.
"Such things do not happen in sport. Having played for so many years, one knows when the time is up."
Ganguly, who made his Test debut in 1996, is the first of India's five veterans -- dubbed the 'fab five' -- to finally put an end to their long careers.
The others are Sachin Tendulkar, 35, who needs only 77 more runs to overtake Brian Lara as Test cricket's leading scorer, skipper Anil Kumble, who turns 38 later this month, Ragul Dravid, 35, and Venkatsai Laxman, 33.
Ganguly was India's most successful Test captain with 21 wins in 49 matches before he was sacked in 2005 following a public spat with then Coach Greg Chappell.
The elegant left-hander has so far scored 6,888 runs in 109 Tests at an average of 41.74 with 15 centuries.
Ganguly finished his one-day career with 11,363 runs in 311 matches, one of only seven batsmen in the world to cross the 10,000-run mark in limited-overs cricket.
India's chairman of selectors Krishnamachari Srikkanth said Ganguly had informed him of his decision to quit earlier on Tuesday.
"He had a good chat with me and fellow selector Narendra Hirwani," Srikkanth, the former Test opener, told reporters.
"He wants a peaceful series without any troubles on his mind. I hope he goes out with a couple of hundreds.
"Ganguly was one of the best captains the world has ever produced and I think he deserves a rousing farewell."
Ganguly, an unpopular choice for his Test debut in England in 1996, silenced his critics with a century in his first match at Lord's.
But he became a cult figure around the country when he led India to a thrilling 2-1 win over Steve Waugh's world champion Australian side at home in 2001.
All seemed lost for India when Waugh's men wrapped up the first Test in Mumbai in three days and made the hosts follow on 274 runs behind in the second match in Kolkata's Eden Gardens.
India, however, conjured up a remarkable fightback on the back of Laxman's extraordinary 281 to win the Kolkata Test by 171 runs and then clinched the series with a two-wicket humdinger in Chennai.
Ganguly also captained India to the World Cup final in South Africa in 2003, where they lost to Australia.
