Tipuric comes in from the bench to start on the openside flank, with only one other change from the side that beat Italy 34-14 last Friday night - Jason Tovey recovering from a calf strain to take up a place at full back.
Wales Under 20 head coach Phil Davies said, "As a management team, we are thrilled with the leadership shown by both Scott Andrews and James Thomas in the games to date. With so many games being played at the Junior World Championship over a short space of time, we needed to identify leaders.
"Justin Tipuric has a lot of experience after being a key member of last season's Under 20 squad and has performed well after coming back from injury. He is a respected member of the squad and it is pleasing that three players will have led the side during this campaign.
"The boys produced a pleasing performance on Friday night in the win over Italy - the Italians had run all the other nations close and we showed a step-up in intensity and a clear improvement on our earlier matches.
"Ireland pose a different challenge. They have some good ball winners and a very good kicking game, and they've only lost one game so far, to Scotland last weekend. However, if we can build on last weekend, do the basics well with a positive attitude, and express ourselves, our performance will follow the attitude I'm sure."
WALES UNDER 20 v Ireland, Friday 20 March, 7.10pm:
Jason Tovey (Dragons); James Loxton (Blues Academy / Glamorgan Wanderers), Scott Williams (Scarlets Academy / Llanelli), Ashley Beck (vice-capt, Ospreys / Aberavon), Nick Reynolds (Llanelli); David Langdon (Dragons academy / Ebbw Vale), Tavis Knoyle (Neath); Aaron Coundley (Dragons Academy / Ebbw Vale), Rhys Williams (Blues Academy / Pontypridd), Scott Andrews (Blues Academy / Glamorgan Wanderers), James King (Ospreys academy / Aberavon), Ashley Sweet (Dragons Academy / Cross Keys), James Thomas (Dragons Academy / Ebbw Vale), Justin Tipuric captain (Ospreys academy / Aberavon), Rory Pitman (Ospreys Academy / Bridgend).
Replacements: Craig Attwell (Dragons Academy / Newbridge), Simon Gardiner (Scarlets academy / Llanelli), Rhys Jenkins (Dragons Academy / Ebbw Vale, Josh Navidi (Blues academy / Glamorgan Wanderers), James Leadbeater (Cross Keys) Rhys Downes (Blues academy / Pontypridd), Matthew Jarvis (Ospreys academy / Neath).
Tickets for Friday night's match are £5 for children with adult tickets at just £7 and £10. Tickets are available from Parc y Scarlets ticket office (0871 871 8088), the WRU shop on Westgate Street, Cardiff and via Ticketmaster (www.ticketmaster.co.uk).