With both sides level on 23 points after 10 games of the regular campaign, the winner of the Ravenhill encounter will significantly enhance their own chances of a top-four spot, while putting a serious dent in the Play Off aspirations of their opponents.
Ulster haven't seen Magners League action since the encouraging home win over reigning champions Munster on January 2 but Henry knows that a similarly positive result is required against the Dragons if they want to close the gap on league leaders Glasgow.
"Our focus is completely on the Magners League now, so the Dragons game is a massive challenge for us," said Henry, who has featured in all bar one of Ulster's league games so far this term.
"A lot of our boys have not been playing so they want to start after a long break.
"We've got the same number of points as the Dragons so this could be make or break for us. It's a massive game."
Ulster will be looking for revenge over Paul Turner's men following a comprehensive 23-6 reverse at Rodney Parade on the opening day of the season.
Henry and co had arrived in South Wales in confident mood after an impressive pre-season but the Dragons soon brought them back down to earth with a bump.
Ulster's skipper admits that the Dragons' stunning win over high-flying English outfit Saracens last weekend is yet another reminder of how dangerous they can be, but he intends to make sure that is his side who enhance their Magners League credentials by close of play tonight.
"We know their players very well and we got a bit of a hammering from them at the beginning of the season.
"We had won our three pre-season games and the mood going into the season was one of excitement. We thought the game there would be a lot closer, but it's a horrible place to go. It's really tough there and they finished us off well.
"They won the battle of the breakdown which is something we've got to get right this time. They use the ball well and they've got some great finishers. They also bring a physicality to the game and they were just smarter than us.
"They've been playing very well again recently, but we've had Andrew Trimble and Paddy Wallace training with us this week and we're very much looking forward to the game.
"I've heard from people who saw their game against the Saracens that it was an awesome performance, quite something, so we know that we're in for a big battle."
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