Coman, who turns 27 later this month, said: "It's a massive honour, we've got an exciting team and I'm really looking forward to the season ahead."
Signing for Edinburgh Rugby during 2013/14 on a two-year deal, Coman is no stranger to the captain's armband.
He said: "The first time I led a team was Nelson Bay under-16s and, more recently, I was captain of Hawke's Bay for the last four years.
"What makes a good captain? Staying calm in tough situations and having an idea of how your players are feeling outside of the game. You have to take care of your playing ability so that the boys can follow - take pride in your performance."
A graduate of Edinburgh Rugby's Elite Development Programme and former recipient of the John MacPhail scholarship, Grant Gilchrist became a full time professional player in season 2011/12. The 24-year-old went on to win his first Scotland cap during the 2013 RBS 6 Nations and led his country in two of this summer's Tests, against Argentina and South Africa.
Edinburgh Rugby head coach Alan Solomons said: "Mike has a lot of experience in a leadership role, captaining his former club Hawke's Bay, and stood in to lead Edinburgh last season when Greig [Laidlaw] was on international duty.
"Grant has come on in leaps and bounds in terms of leadership and this will be another step in developing those qualities.
"I look forward to working very closely with them both."
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