A Cloaking Device is an item in Super Smash Bros. Melee that makes the user invisible. Damage is not dealt while a character is invisible (not even self-damage), but knockback still applies, meaning invisible characters can still be KO'd. While invisible, each opponent KO'd will add points for an Invisible KO bonus. The invisibility lasts 10 seconds. Slippy hints in one event match that the Cloaking Device is of his own invention; however, the trophy and look of the device makes reference to Perfect Dark.

Using names allows an invisible player to easily track themselves, as the tag is still visible while cloaked, as well as any personal items they use, such as Mario's cape in Brawl, or Snake when he uses Cypher. Characters themselves are not completely invisible - the cloak flickers about one every three or four seconds, and the faster a character moves, the more obvious they become (becoming temporarily completely visible when attacking). The transparency effect is generated by environment mapping, which also makes the character's outline visible when in front of any opponent, item, or special effect.

Super Smash Bros. Melee trophy.

Since players are unable to see their own cloaked characters, the primary benefit of the item is the damage immunity. Computer-controlled characters are not affected by the Cloaking Device and continue fighting as if the opponent was not cloaked at all.

While the item itself is absent, in Super Smash Bros. Brawl's Special Brawl mode, a modifier named "Clear" is available. Turning this option on makes all characters invisible, similar to the effect caused through use of the Cloaking Device. However, the Cloaking Device itself does not return (most likely its affiliation with the now-Microsoft-owned Rare), and no new item was introduced to replace it.

Additionally, in Co-Op Event 6: Unwanted Suitors, the opponents will be invisible in the same way.

Similar to when the Nintendog is summoned, name labels will also be hidden during clear Brawl.