Alphinaud is a self-assured young man, calm and mature for his age.

He shows more interest in intervening in the events of Eorzea than his sister, who prefers to watch history unfold from the shadow. Charismatic and diplomatic, he finds it easy to gain the Eorzea Alliance leaders' trust, partly thanks to his grandfather's credit. Alphinaud has a big ego, and often clashes with other nations' leaders about their ideals. This shortcoming later proves fatal when half of the Crystal Braves is bribed into betraying him with Alphinaud unknowingly walking into their trap.

Initially Alphinaud participates in Eorzea's affairs with his own agenda: to find out what happened to his grandfather and finish what he started to test his potential and prove himself. As he spends more time with the Scions in Eorzea, he comes understand why his grandfather sacrificed so much for the realm, and resolves to follow in his footsteps.

Alphinaud is not invulnerable to negative feelings, as he laments his failure in the final act of A Realm Reborn, regretting his mistakes and overconfidence. He also easily gets flustered whenever Krile or Alisaie threaten to regale embarrassing details from his earlier days in the Studium in front of the Warrior of Light.