The 25 year old will lead his province out for the first time this season when they take on Leeds in a friendly at the Sportsground next Saturday (kick off: 6.30pm).
The Portumna native, who has represented Ireland at Youths, U-19, U-21 and A levels, said he is thrilled with the honour.
"I consider it a great honour to play for my province so to be asked to captain the side makes it even more special," said Muldoon.
Connacht have lined up four pre-season friendlies at the Sportsground, starting on Saturday with the visit of Leeds on Saturday August 9th (kick off: 6.30pm), followed by Harlequins the following Saturday, London Welsh on Friday, August 22, and against Queensland Reds on Tuesday, August 26th.
"It will be a good build-up and pre-season training has gone well and we are all looking forward to the start of the Magners League next month," said Muldoon.
Muldoon, a former Galway minor hurler, is now in his seventh year with Connacht.
Coach Michael Bradley said that Muldoon was a great example to younger players coming through.
"We're delighted John has accepted the captaincy for the 2008/09 season. He's a player who has always led from the front based on his workrate in training and on matchday.
"He has developed into a key player in the squad over the past number of seasons and has been excellent for us both in terms of his consistency of performances and his strength of character," he said.
Muldoon made his competitive debut for Connacht in 2004 at the Sportsground against Border Reivers and the flanker has gone from strength to strength since then.
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