Ulster currently occupy the final play-off spot in the table, five points ahead of fifth-placed Ospreys.
And back rower Henry admits the home tie against RaboDirect PRO12 leaders - and Irish provincial rivals - Leinster is the perfect chance to lay down a marker.
"It's do or die time; we know we need points, desperately," Henry told the Irish Times.
"Leinster are a side that know how to finish the end to a season very well and that's something we are going to have to counter.
"We have to let Leinster know early on that this is our home patch and that they're in for a game. There are obviously other motivational factors, such as the new stand and players leaving at the end of the season; we will use every bit we can (to draw out a performance).
"Every provincial game is hugely confrontational. Then there is also the one-on-one battles that are coming this weekend."
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