Stephen Ferris is also back from international duty, lining out at blindside flanker alongside David Pollock and Ulster captain Chris Henry.
There are four other changes, with Scottish winger Simon Danielli, half-backs Niall O'Connor and Paul Marshall and lock Dan Tuohy all starting.
Belfast Harlequins and Ireland Under-20 scrum half Michael Heaney could also make his senior bow for Ulster off the replacements bench.
With his side looking to bounce back from their recent 25-8 loss to the Scarlets, Ulster coach Brian McLaughlin said: "It's a big challenge at Cardiff, especially after the very disappointing display at the Scarlets.
"We're really looking forward to getting ourselves back on track and moving in the right direction.
"We started quite well against the Scarlets, but we just made too many simple schoolboy errors.
"We put ourselves under ferocious pressure from the amount of errors we made, the soft points we gave away and the lack of discipline with regard to the referee.
"The squad all sat down last Friday, which was the first time we were all back together after the internationals although we were missing Paddy, Rory and Stephen.
"We sat down and had a good chat about the Scarlets game, we went through the review of the game and there were a few home truths, there's no doubt about that. After that hopefully we'll see a much more focused and more determined performance this week."
He added: "We've had two good training sessions so far this week, we had a good session on Monday.
"We got everybody back in on Tuesday and we had a good attack session on Tuesday morning. We're building up nicely and we just hope we can go to Cardiff and put up a display that we're proud of.
"This is the first time since Bath we've had everybody available, so we're looking forward to getting over to Cardiff and showing how good a team we really are."
The following players were not considered this week due to injury: Justin Fitzpatrick, Matt McCullough, Cillian Willis, Ian Porter, Adam Macklin, Bryn Cunningham and Willie Faloon.
ULSTER (v Cardiff Blues): Jamie Smith; Andrew Trimble, Darren Cave, Paddy Wallace, Simon Danielli; Niall O'Connor, Paul Marshall; Tom Court, Rory Best, BJ Botha, Dan Tuohy, Ryan Caldwell, Stephen Ferris, David Pollock, Chris Henry (capt).
Replacements: Nigel Brady, Declan Fitzpatrick, Ed O'Donoghue, Robbie Diack, Michael Heaney, Ian Humphreys, Timoci Nagusa.