The cast of ''Manga/FullmetalAlchemist'' have so many recorded Berserk Buttons that it practically requires separate folders for each one.
[[folder: Edward Elric ]]
* Perhaps Ed's most famous Berserk Button is any mention of his [[TheNapoleon vertical deficiencies]]. He usually ends up exaggerating the insult to ridiculous extremes as well as whooping the ass of the offender. The only one he won't go nuts on is Al (after all, they're brothers...and someone has to keep him in line), and even ''he'' got away with a knock on the head and a retort of "Don't call me small." Of course, the short rants are constantly a CrowningMomentOfFunny.
** Take note, at one point, he thought to himself that he was lucky being so small made it easy for him to crawl through air ducts. ''He had to fight the urge to punch himself in the face.''
* Also, don't suggest that [[SheIsNotMyGirlfriend Winry is his girlfriend.]]
[[folder: Winry Rockbell ]]
* Edward finds himself the victim of Winry's Berserk Button whenever he needs to go back to her for maintenance and (predominantly) repairs. If there's even so much as ''one scratch''...
* Also, never criticize her handiwork. After hearing someone insult her automatic craftsmanship in the first anime, Winry goes from telling Ed to calm down to telling Al to let Ed go so he could (more or less) kick the guy's ass.
[[folder: Roy Mustang ]]
* He doesn't take kindly to being reminded that he's useless when wet (due to his PlayingWithFire powers fizzling out under those circumstances).
[[folder: Izumi Curtis ]]
* Izumi seems to have a few of these, and they seem to be set on a hair trigger. Don't call her old. Or hit on her when her husband is around. Just because he's a GentleGiant doesn't mean he can't beat you to a pulp when provoked.
[[folder: Other characters ]]
* Don't mess with Roy when Riza Hawkeye is around. Or vice versa.
* A scene with Greed in the manga shows that calling Envy "ugly" is a great way to tick him off, and get him to turn into his true form to ''kill you''.
* In the first anime, mentioning [[spoiler:Hohenheim]] is a great way to have your face pounded in by Envy.
* Ed and Al share a minor (in Al's case, not so minor for quite a while) one that is labeled "Pointing out how GREAT it actually is being a soul trapped in a suit of armor". It led to one pretty not-so-nice brotherly fight.
* Do NOT bring up the human transmutation incident with either of the brothers. Especially if you're doing it to claim that they're [[NotSoDifferent no different than you]]. This one very nearly got Shou Tucker killed when the two learned of [[spoiler:his horrible act of fusing his daughter Nina with her dog]], shortly before [[spoiler:Scar killed him and put his chimera out of its misery]].
* Ling gets pretty pissed whenever someone, especially those in positions of power such as [[spoiler:Fuhrer Bradley]], try to convince him that leaders should be able to [[YouHaveOutlivedYourUsefulness abandon their followers]].