Ace had a tendency to never back down from a fight, saying that he would never run once facing an enemy.Because of this, some people believed that Ace had a death wish, but in truth he wanted to prevent people he cared for from getting hurt.He also wore a short second belt with a large red "A" on the silver buckle over his right hip, but left it unfastened and threaded the free end along the back of his shorts. On Ace's left arm, he wore a Log Pose and a red and white striped bracelet around his wrist, an orange elbow guard, and his "ASCE" tattoo.
Ace commented upon his own death that he had never sought fame or fortune - all he had wanted was the answer to his lifelong question of whether or not he should have been born, as this was the only thing preventing him from dying with no regrets as he and Luffy had vowed to do so and the fact he had a younger brother to look out for.
Ace's only regret was that he would not live to see Luffy achieve his dream, which he believed Luffy undoubtedly would accomplish as he was his little brother.
He also sported rather childish freckles (inherited from his mother), and tended to make a skeptical facial expression by raising his left eyebrow.
Interestingly, his facial features were almost akin to his biological father Gol D. Ace's tattoos were among his most remarkable, trademark features.
Although they were not blood related, Ace looked remarkably like his foster brother, Luffy.
However, Ace was more serious looking than Luffy's lighthearted design, and was also taller and more muscular.
In addition, Ace liked to party as much as his brother does.
When he boarded Buggy's ship, he was drawn by the smell of food and decided to enjoy himself while he was there. He tended to randomly fall asleep while eating and conversing, leaving strangers around him wondering if he had died.
Ace wore an open-front shirt until he received Whitebeard's tattoo - afterwards, he stopped wearing anything over his upper body except when on winter islands.
He wore black boots, black knee-length shorts with an eyelet-studded orange belt, and a blue pouch belted around his left leg.
Ace was always seen wearing dark brown, flat, slipper-like shoes, and in the winter, he wore a green cardigan over his normal clothes.