The Ulster skipper was voted Magners Personality of the Year, the Magners League Rugby Writers' Player of the Year and the Ulster Rugby Supporters Club Outstanding Player of the Season.
Henry stepped up to the role of captain at short notice after club skipper Rory Best was ruled out for most of the season with a neck injury.
The No8's impressive form for his province saw him lead the Irish Wolfhounds against Scotland A and he has since been rewarded with a call up to the Ireland senior squad for the summer tour of Australasia.
The 25-year-old featured in 15 of Ulster's 18 Magners League games this season, playing the full 80 minutes in 10 of those fixtures and only once being substituted before the hour mark.
Henry has now made 31 appearances for his province, although he will have increased competition for a place in the middle of the back row next season with the arrival of former All Black star Xavier Rush from Cardiff Blues.
Andrew Trimble won the evening's other main award, picking up the Bank of Ireland Ulster Player of the Year title.
Trimble reached a century of caps in all competitions for Ulster this season and took his Ireland tally to 27 during the 2010 Six Nations.
The 26-year-old scored five tries for Ulster this term, with three of those coming in his 15 Magners League appearances.
He adds the award to the Irish 'Try of the Year' accolade he won recently for his effort against Bath in the Heineken Cup.
Former Ireland and Lions legend Jack Kyle was also honoured as he became the first inductee into the Irish Rugby Football Union Ulster Branch Hall of Fame.
Arguably his country's greatest ever player, Kyle was the creative genius behind Ireland's first Grand Slam triumph in 1948.
Kyle won six Test caps for the Lions two years later and went on to make 46 appearances for his country across 11 seasons before retiring in 1958.
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