The 34-year-old will win his 95th cap and wear the armband in the absence of No8 Ryan Jones, who has a calf injury.
Coach Warren Gatland said: “This is an opportunity for Martyn, who is one of our key leaders, to captain Wales again and rise to that challenge after doing a good job against Scotland last year.”
Gareth Delve makes his second Test start in place of Jones, while hooker Matthew Rees returns in place of Huw Bennett. Lock Luke Charteris also comes in for Deiniol Jones.
Meanwhile, Ireland captain Brian O’Driscoll will earn his 100th international cap after coach Declan Kidney announced an unchanged starting side.