Wales were beaten 27-17 by Ireland in Dublin in their last encounter but were roundly praised for an improved showing, as they were in a last-gasp 26-23 home defeat to Scotland in the previous round.
Tandy has decided on continuity to reward the players who did duty in Ireland as they try to break their barren run and finish the campaign on a high.
Dan Edwards and scrumhalf Tomos Williams make up the halfback pairing, with Joe Hawkins and Eddie James in the midfield, and a back three of wings Josh Adams and Ellis Mee, and Louis Rees-Zammit in the fullback jersey.
Captain Dewi Lake has props Rhys Carre and Tomas Francis either side of him in the front row, with Dafydd Jenkins and Ben Carter the lock pairing, and a loose trio of number eight Aaron Wainwright, Alex Mann and James Botham.
"Having an unchanged team, I think it reflects the cohesion and the consistency in the group and the consistency of performance out in Ireland,” Tandy said.
"This week we need to go up another level. We've had some really good performances. I think there were parts against France, then we built up into the Scotland game where I thought we were very good.
"Against Ireland we stepped up to the plate physically. Now it's putting it all together and creating our best performance this weekend."
Italy have won on their last two visits to Cardiff and three of their previous four tests against Wales. They are coming off a historic first-ever win over England last weekend.
Wales team:
15-Louis Rees-Zammit; 14-Ellis Mee, 13-Eddie James, 12-Joe Hawkins, 11-Josh Adams; 10-Dan Edwards, 9-Tomos Williams; 1-Rhys Carre, 2-Dewi Lake (captain), 3-Tomas Francis, 4-Dafydd Jenkins, 5-Ben Carter, 6-Alex Mann, 7-James Botham, 8-Aaron Wainwright.
Replacements: 16-Ryan Elias, 17-Nicky Smith, 18-Archie Griffin, 19-Adam Beard, 20-Olly Cracknell, 21-Kieran Hardy, 22-Jarrod Evans, 23-Blair Murray.