There is an unused track that can be accessed from within the game as "FGM #94" in the Sound Test. This theme was later remade for Kirby Triple Deluxe, and used in the Cave section of Fine Field.

The miniboss Blocky seems to be a reference to the enemy Rocky from the Eggerland series.

In the bad ending credits, Sir Kibble is referred to as "Load Kibble". This was probably intended to be "Lord Kibble", as its keychain in the Japanese version of Kirby Triple Deluxe reflects this (ロードキブル).

In stage 5-5, using Kine and the spark ability in one of the dark rooms will reveal a picture of a orca in it. The image bears a strong resemblance to the boss Acro from Kirby's Dream Land 3 and Kirby 64: The Crystal Shards. However, as Acro is never seen in-game, this may hint that he was originally intended to make an appearance but was scrapped and moved to later games. He can also be seen on one of the proposal documents of Kirby's Dream Land 2 in Kirby's Dream Collection.

The image seen in the Sound Test mode is a recreation of a scene from "Famicom Mukashibanashi Yūyūki", a text-based adventure game for the Famicom Disk System by Nintendo EAD.

In the Japanese version of the game, the character Chao from the Japan-only game, Famicom Mukashibanashi: Yūyūki (ふぁみこんむかし話 遊遊記) can be found in a bag that is guarded by a mid-boss. She can only be found in the bag if the player already has the corresponding animal friend. She has a very low chance of showing up, and when she does, she gives you an extra life and adds 1% to the game's completion, making it necessary to find her to get 100% completion. She is replaced by Gooey in the international versions.

There's a doodle of a naked women hidden in the background of the level Red Canyon 5-5.