This is a list of allusions found throughout Assassination Classroom.
- The surnames of the students of Class 3-E are derived from the surnames of most of the ronin in the story of the Forty-seven Ronin. Gakuhō Asano's surname is derived from Asano Naganori, the daimyo whom the forty-seven ronin avenged.
- When Korosensei drinks Okuda's poison, his head turns into Sonic's with horns.
- There's a panel where Raoh from Fist of The North Star is shown while looking at a Shooting Star.
- The poem in back is Shooting Star by Tōson Shimazaki.
- American Commodore Matthew Perry is visualized in a seduced appearance as Irina explains to class 3-E the importance of learning how to seduce foreigners.
- Nakamura and Okajima are also seen dreaming of Jack Sparrow from Pirates of the Caribbean and Lara Croft from Tomb Raider.
- Korosensei wears a headband with the symbol of Konohagakure to indicate to Terasaka that he is "weak in multiple subjects", similar to Naruto.
- Two of Korosensei's duplicates present themselves to Kimura dressed up as Mickey Mouse and Doraemon.
- Kanzaki visualizes Ryuk from Death Note with a ruined face of Jesus identical to that of the fresco painting Ecce Homo, restored in 2012 by amateur Spanish artist Cecilia Giménez.
- Kanzaki is seen playing Dance Dance Revolution in the past.
- Red Eye imagines numerous red objects inside his sniper's scope, including Elmo, Mario's hat, and a Japan Post mailbox.
- One of the actors of the samurai show, who is defending a woman, wears a scar and says he wouldn't hurt people. It is likely a reference to Kenshin Himura from Rurouni Kenshin, a samurai with the same scar, who doesn't like hurt the others if he can and refuse to kill.
- The sweets shop navigation system installed by Korosensei into Ritsu has donuts pointing to Australia and Canada, possibly implying locations for Donut King and Tim Hortons.
- Medama-oyaji from GeGeGe no Kitarō can be seen on the blackboard as Korosensei gives a lesson on eye structure.
- Irina shows a clip to class 3-E of Samantha and Carrie talking from Sex and the City.
- The silhouette of the unkillable monster Lovro envisions has a pose resembling that of Mewtwo from Pokemon, but with extra claws and horns added. The man in front of it wears the same clothes as Ash.
- When it is revealed Korosensei and Itona are "brothers", they're subsequently visualized in a series of panels as part of other famous brother duos in their respective roles. The second panel consists of Sazae Fuguta and (sister of) Katsuo Isono from Sazae-san. The third panel consists of Takehiro Donoue (number 63) and Naomichi Donoue (number 1) from the Chunichi Dragons, a Japanese professional baseball team. The last panel consists of Raditz and Goku from Dragon Ball Z.
- Shiro can be seen reading volume 3 of The Disaster of Kusuo Saiki.
- Korosensei is seen resting with a cola drink with the logo's font similar to that of Coca-Cola.
- Korosensei is making a Kracie Nerune meal while in baseball form.
- Sugaya recalls making a drawing of Dutch painter Rembrandt on the back of an assignment.
- Korosensei tries to feed Irina a stick of Pooky, a spoof of the real-life Pocky.
- Korosensei is dressed up like Jiro Horikoshi.
- When Fuwa declares Smog to be the culprit who spread the virus, she does so in a manner inspired by Yako Katsuragi from Majin Tantei Nōgami Neuro, Yūsei Matsui's own previous serial. She then explains to Nagisa and Kayano how reading shonen manga makes her adapt to unusual situations, recalling a moment in class when she was daydreaming of meeting Ryuk from Death Note. She then expresses her love of mystery manga, especially from Weekly Shōnen Jump competitors Weekly Shōnen Magazine and Weekly Shōnen Sunday. When Nagisa questions her about Jump, she mentions she might want to buy the new paperback edition, again referring to Majin Tantei Nōgami Neuro and its newly released paperbacks, to which Nagisa and Kayano become shocked over this tongue-in-cheek promotion.
- When Korosensei forbids Chiba and Hayami to use real guns in order to hurt or kill someone, he wears a scar which is the same as Kenshin Himura from Rurouni Kenshin.
- The usefulness of the Nekodamashi in a fight is compared to the tarot cards of the moon, the fool and the chariot.
- Karasuma was briefly portrayed as the Colossal Titan, a prominent character from Shingeki no Kyojin/Attack on Titan.
- Takebayashi's curse is represented by a heart wrapped in chains. It can be a reference to Kurapika from Hunter x Hunter, who has a chain on his heart. This technique is considered as very bad and dangerous.
- Terasaka cosplayed as Nogami Neuro from Majin Tantei Nougami Neuro.
- Korosensei says he was reading Hunter x Hunter and Toriko before Chiba stained his Weekly Shōnen Jump.
- Korosensei is seen cosplayeing as Doraemon, a tentacle in his pocket, when the God of Death explains he needs more information on him. Matsui used Doraemon's pocket to illustrate Korosensei's unknown abilities.
- The students visualize the confrontation between Karasuma and the God of Death as a fight in Godzilla movies.
- Page 2, we can see Tetsuya Kuroko from Kuroko's Basket, Kusuo Saiki from Saiki Kusuo no Ψ Nan and Takeo Gouda from Ore Monogatari waiting for food.
- On the first page, Nagisa and Karma are represented as the Death and Devil tarot cards respectively.
- The picture of Korosensei's clone between a temple is a reference to a TV show called Yuku Toshi Kuru Toshi (which can be translate by "A year departing and a year coming") which shows live scenes at different temples.
- The "He was ridiculous!" is a phrase of Nakanishi Takahiro which has became an Internet meme.
- One of Korosensei's clone wears a wig with short bangs and a headband on which there is "I cut my bangs too short!", a reference to Mito Natsume's song "I cut my bangs too short".
- Fuwa imitates Luffy's Gear Second pose.
- A reference is made to Jojo's Bizarre Adventure when a painting used as target practice appears in the style of the stand Thoth; further referencing a picture where the main character Jotaro Kujo is shot by two bullets (in this case, the character on the painting was Korosensei).