Trimble, a graduate of the Hughes Insurance Ulster Rugby Academy, made his senior debut for Ulster against Cardiff Blues at the Arms Park on 9th September 2005.
The 28 year old has made 155 appearances for the Province and has scored an Ulster record 50 first team tries. He is on track to break his personal record of ten tries in one campaign, having scored eight tries for Ulster so far this season.
Trimble made his Ireland debut against Australia at Lansdowne Road in November 2005. He has won 49 caps and has scored 11 international tries. His last appearance for Ireland was against South Africa in the Guinness Series in November last year.
Commenting on Andrew Trimble's new contract, Ulster's Director of Rugby, David Humphreys, said: "I am delighted that Andrew has signed a new national contract as he is, without doubt, a world-class finisher and a hugely important member of our squad.
"Andrew has now spent almost eight years at Ulster Rugby. This deal will take him to a decade at Ravenhill and that reflects both his remarkable consistency of performance and his unwavering commitment to his Province."
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