* The tune that plays whenever Troff and Scoff open a boss door is actually from ''VideoGame/BanjoKazooie'', where it plays whenever Banjo enters an area containing a Stop 'n' Swop item. Part of it also sounds like the tune that plays when Dingpot fills all of your items in ''Banjo-Tooie''; worth noting is that this theme still predates ''Donkey Kong 64'', as it was DummiedOut of ''Banjo-Kazooie''.
* GenreKiller: Depending on who you ask, it killed off the [[GottaCatchEmAll collectathon]] [[PlatformGame platformer]] because OneHundredPercentCompletion took so long that most people who managed it had had enough of that style of gameplay to last for years, or it killed the genre by causing people to get completely sick of it.
* HeyItsThatVoice: Donkey Kong is [[BanjoKazooie Mumbo Jumbo]].
* KeepCirculatingTheTapes: For many years, fans were left speculating as to why Nintendo hadn't rereleased this game on the Virtual Console. While Nintendo, not Rare or Microsoft, owns the rights to the game because they created Donkey Kong, many speculated that the inclusion of Jetpac, an original Rare IP that is now owned by Microsoft, prevented the game's re-release. However, Nintendo finally rescued the game in April 2015 when it was announced it as one of the first [=N64=] games to hit the Wii U Virtual Console.
* NamesTheSame: [=DK64=] level "Crystal Caves" shares a name with a song in ''[[VideoGame/YoshisIsland Super Mario World 2]]''. [[ExactlyWhatItSaysOnTheTin That plays in cave levels.]]
* ThrowItIn: The DK Rap was originally written as a joke by Grant Kirkhope, but the developers liked it enough to include in the game.
* UrbanLegendOfZelda: Several, the most notable being an inaccessible room in Creepy Castle with a glass wall. If you stand on the hallway outside of it and use a first-person perspective, you can see a tall, carved stone pillar with a Monkeyport (teleportation) pad for Tiny nearby as well as a purple banana balloon floating over it. The room appears to be useless. King K. Rool's control room also features five steel kegs with the Kongs' faces painted on them. Probably nothing more than a little detail, but it sparked some speculation back in the day.
** Until people learned how to get to the room. The Monkey Port pad is in the Stock Car Race room across the hall, behind the Frantic Factory model. In order to get into ''that'' room, you need to get Tiny into the ballroom. All Tiny has to do to get in there is have Diddy open the door and switch characters before it closes.
*** [[EmptyRoomPsych Then people began to question why a room that required that much effort to get to was empty, which lead to more rumors.]]
** The fact that this was the first Donkey Kong game since VideoGame/DonkeyKongCountry not to feature a Lost World sparked a lot of urban legends back in the day.
* WhatCouldHaveBeen: Some text in the game's coding and an [[https://www.youtube.com/watch?v=kOAATfDXfuY unused cutscene]] suggest that this could've been compatible with ''[[VideoGame/BanjoKazooie Banjo Tooie]]'''s scrapped Stop 'n' Swop feature.
** Fungi Forest was going to appear in ''Banjo-Kazooie'' as Fungus Forest, but the level was (among other levels) scrapped from that game due to time constraints. A picture of Fungus Forest can nevertheless be seen in Banjo's house.
** The game as a whole was initially planned for the 64DD add-on, but repurposed for cartridge after that peripheral's failure.