Ganguly, 34, who played his last One-dayer in September 2005 in Zimbabwe, was included in a 15-man squad for the first two matches of a four-game home series against the West Indies later this month.
The seasoned left-hander was rewarded for a successful comeback in Test cricket on the recent tour of South Africa where he emerged India's leading scorer with 214 runs in three matches.
Swashbuckling opener Sehwag, who averaged just 14.80 in his last 10 One-dayers, was axed for the two matches but was retained in a 30-man preliminary World Cup squad also named on Friday.
Chairman of selectors Dilip Vengsarkar said both Sehwag and all-rounder Irfan Pathan were left out for the West Indies matches so they could play domestic cricket to regain form before the World Cup.
"They are important players but both have been out of form for some time," said Vengsarkar, a former Test captain and prolific batsman.
"They need to sort out their cricket. I am sure both Sehwag and Pathan will come back strongly."
Vengsarkar said the selectors were worried by India's poor run in limited-overs cricket, which has seen them win just two of their last 10 matches including a 4-0 drubbing in South Africa.
Eight of the 17 players who were involved in the One-dayers in South Africa have been excluded for the matches against the West Indies, including batsmen Mohammad Kaif and Venkatsai Laxman.
Seamer Joginder Sharma, 23, and opening batsman Robin Uthappa, 21, have been recalled after a string of good performances in domestic cricket.
Sharma played three One-dayers in Bangladesh in 2004 before being dropped, while Uthappa played the last of his three matches on the West Indies tour in April-May last year.
The team includes four openers in Uthappa, Gautam Gambhir, Sachin Tendulkar and Ganguly, but Vengsarkar said it was still undecided who will open the batting against the West Indies.
Tendulkar and Ganguly form the most successful opening pair in One-day history with 5,621 runs in 117 matches.
Tendulkar is the leading batsman in the shorter version of the game with 14,537 runs, while Ganguly is one of only five batsmen to score more than 10,000 One-day runs.
The first two One-dayers against the West Indies will be played in Nagpur on January 21 and Cuttack on Jan 24.
The teams for the last two matches in Chennai on Jan 27 and Vadodara on Jan 31, four further home games against Sri Lanka from February 8-17 and the World Cup will be picked later.
India must name their final World Cup squad of 15 by February 13.
Team for first two West Indies One-dayers: Rahul Dravid (capt), Robin Uthappa, Gautam Gambhir, Sachin Tendulkar, Sourav Ganguly, Mahendra Dhoni, Dinesh Karthick, Suresh Raina, Zaheer Khan, Shanthakumaran Sreesanth, Ajit Agarkar, Joginder Sharma, Rudra Pratap Singh, Ramesh Powar, Harbhajan Singh.
World Cup 30-man preliminary squad: Rahul Dravid, Virender Sehwag, Sachin Tendulkar, Yuvraj Singh, Mohammad Kaif, Gautam Gambhir, Sourav Ganguly, Robin Uthappa, Joginder Sharma, Ajit Agarakar, Mahendra Dhoni, Rudra Pratap Singh, Dinesh Karthick, Suresh Raina, Zaheer Khan, Shanthakumaran Sreesanth, Ramesh Powar, Harbhajan Singh, Irfan Pathan, Munaf Patel, Anil Kumble, Dinesh Mongia, Vikram Rajvir Singh, Parthiv Patel, Venkatsai Laxman, Rohit Sharma, Ishant Sharma, Cheteswar Pujara, Subramaniam Badrinath, Rajesh Powar.