They are currently fourth in the table with two rounds remaining although fifth-placed Scarlets are breathing down their neck just two points back.
Ulster have beaten table toppers Leinster just once in their last seven meetings, but that victory came 12 months ago when they scored 26 unanswered points to triumph 26-10.
And Best insists Ulster, whose only defeat at Kingspan Stadium since early January was 20-21 to Scarlets in round 15, can approach the game full of confidence.
"Leinster are a quality side of course. Being from Ireland and playing on the international scene, I know so many of their players so well. We all do," he said.
"We know how good they are - but for us a lot of the challenges are around ourselves to ensure we perform.
"And we know, especially at home, if we perform to the best of our ability, that we are very, very hard to beat.
"And we know against a quality side like Leinster, we have to produce that this weekend."
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