Originally, Zero was a redesign of the Mega Man character as portrayed by the lead artist, Keiji Inafune. However, Zero looked too different from the original Mega Man so, fearing a negative reaction from fans, Inafune gave him a new name and a secondary role to the new Mega Man X, who was then designed to be more similar to the original Mega Man.

In Mega Man X, it is possible to learn the "Hadoken", Ryu's signature move from the Street Fighter series. After beating the game, obtain every Sub Tank, Life Up and Armor Parts. Then play through Armored Armadillo's stage until the last rolling platform. As the platform bursts out of the tunnel and through the sky, dash-jump off of the platform and ascend the wall right on top of the gate to Armored Armadillo. There you will find Dr. Light wearing a Karate uniform. He teaches X the technique.

The enemy Batton was an enemy that appeared in several classic Mega Man games, starting with Mega Man 2. In Armored Armadillo's stage, a single Batton can be found among the Batton Bones, the X series replacement for the Battons. Chronologically speaking (and excusing the enemies abilities to respawn when off-screen), this could be the last accounted Batton in the Mega Man universe.

By viewing the demo then putting in a certain password to trigger a bug where you start at Central Highway but with all Heart Tanks, Sub-Tanks, Weapons, and all the Mavericks defeated, once you complete the intro stage you can go straight to Sigma's Fortress.

If you use the boomerang cutter when fighting Flame Mammoth you can cut off his trunk so he can't shoot the oil slicks.

On the U.S. box art for both the PC and SNES versions, Launch Octopus can be seen with a purple color instead of his red color seen in the game.

The Homing Torpedo weapon is misspelled as "Horming Torpedo." This was fixed in Mega Man Maverick Hunter X.

The intro segment of the boss theme is very similar to the stage select screen theme from Mega Man 2.

According to planner Sho Tsuge & designer Kazunori Tazaki, before the game's title, Mega Man X, was chosen, it was first named Super Rockman as a working title.

Contrary to popular belief that Vile's character design was inspired by bounty hunter Boba Fett from the Star Wars franchise, and that his Japanese name VAVA (ヴァヴァ) was changed to Vile for the international release out of fear of a lawsuit from Lucasfilm (due to the letters "B" and "V" sometimes being used interchangeably in Japanese causing the name to appear too similar to "Boba"), Capcom character designer TOM-PON stated in a 2012 interview that VAVA's design was actually inspired by the character Bubba Zanetti (ババ・ザネッティ, transliterated as Baba Zanetti) from the 1979 film "Mad Max". Coincidentally, as VAVA is renamed Vile outside Japan, this would also result in Dr. Weil's name being transliterated as such from Dr. Vile in order to avoid confusion with him.

In Mega Man X8, Vile's primary color scheme was intentionally changed from purple to green, which more closely resembles Boba Fett, and may be a reference to their similarities.