In Japan, McDonald's once sold demo discs of PaRappa the Rapper 2 and Ape Escape 2001 to promote the games in Japan. The PaRappa demo reskinned the Toasty Buns stage to take place in a McDonald's, while the Ape Escape demo included the first 2 and a half stages, added McDonald's buildings and blimps to the level backgrounds, and added McDonald's food as collectible items - it also included a bonus video of Japanese celebrity Papaya Suzuki exploring New York with a man in a Pipo Monkey mascot costume.

Beard Burger Master voice actor Ethan Eubanks has claimed that the non-rhythmic quips that Beard Burger Master says between lines in his song were not part of the script, and instead improvised. The line "My buns are very toasty" was intended as a mild innuendo, of which Eubanks is not sure if the developers of the game caught on to.

During development of PaRappa the Rapper 2, the Boxy Boy tutorials at the start of each stage were referred to as "Rodney Levels" in reference to character designer Rodney Greenblat's difficulty playing Um Jammer Lammy. Greenblat has said that Masaya Matsuura intended it as a compromise after Um Jammer Lammy proved to be too hard for the children it was aimed at, but he still wanted to implement complex button patterns.

Two lyrics in PaRappa the Rapper 2 were censored for the US release - "We cook the best, tastes better than wine!" was changed to "We cook the best, you better get in line!" in Toasty Buns, and "I am the lord, everybody knows my name" was changed to "I am the man, everybody knows my name" in BIG and it's reprise in Food Court.

Typically, the tutorial for Vs. Mode in PaRappa the Rapper 2 will play the Awful version of whichever stage has been selected in the background, the Bad version for the Boxy Boy tutorial, and then the Good version for the actual gameplay. The exception to this is Always Love, which has completely different songs used in Vs. Mode instead of its actual Bad and Awful songs, it is unknown why the Vs. Mode Bad and Awful versions are different, with possible theories being the Vs. Mode remixes being scrapped but left in Vs. Mode, or Always Love's actual Bad and Awful remixes being considered unsuited for the Vs. Mode due to being versions of the same song with less instruments instead of a completely different song like on all other stages, leading to the creation of new songs. This mysterious track is also used on the map screen when Always Love is highlighted.

Despite retaining "the Rapper" in its title and its source material being a music game, PaRappa only ever raps once in the anime adaptation of the PaRappa the Rapper franchise - that being the penultimate scene of the final episode, with the song sung being a rendition of PaRappa the Rapper 2's final stage, Always Love.

There is an unused 7th stage in PaRappa the Rapper, which seems to be an encore of the final stage where audience members - including PaRappa's rival Joe Chin - come on stage and copy PaRappa's rhymes instead of the other way around. This concept would be used in PaRappa the Rapper 2 as an encore following the final stage's Cool Mode.

PaRappa the Party Mix is a music album that was released in Japan to promote PaRappa the Rapper 2, containing a mix of PaRappa 2 music and mainstream rap songs. Despite being a tie-in for a family-friendly video game series, many of the songs contain adult elements common with mainstream hip-hop, such as violent, sexual, misogynistic, and vulgar lyrics, as well as uses of the colloquial ethnic slur "nigga".