List of Diary of a Wimpy Kid characters

Rowley Jefferson's parents, Robert and Linda, are portrayed as caring but very protective, often acting as a counterbalance to Greg Heffley’s reckless influence. Robert is a defensive father who tries to shield his son from violent media and Greg's schemes, frequently standing in the way of the boys' friendship. Linda's protective nature is evident when she hides healthy ingredients in junk food and makes Greg apologize for injuries he inflicts on Rowley. Linda, however, is usually more tolerant of Greg, even though she ultimately supports her husband's rule against him visiting their home. In the live-action film adaptations, Robert is primarily portrayed by Alfred E. Humphreys, with Kaye Capron and Bronwen Smith portraying Linda.

The extended Jefferson family highlights the difference between Rowley's sheltered upbringing and Greg's cynical view of the world. Rowley's grandfather, affectionately known as "Bampy," serves mainly as a comedic element to showcase Greg's social awkwardness, especially when Greg makes an inappropriate remark about his grandfather's mortality during a birthday party. The Jefferson family is used throughout the series to showcases Rowley's innocence and overbearing parental environment that shaped his naive personality, creating a sharp narrative contrast with the more chaotic Heffley household.

Greg's classmates mainly reflect his continuing attempts to become popular and maneuver on the middle school social ladder. The top of this hierarchy is occupied by students such as Bryce Anderson, who is effortlessly popular with girls, and Holly Hills, whose romantic infatuations with Greg continue for several books. His older sister serves a similar function as a teenage love interest for Greg's older brother, Rodrick. On the flip side, Greg constantly antagonizes classmates who make his school experience miserable. His difficult relationship with demanding, aggressive student Patty Farrell is only one example of his misfortunes. Similarly, Greg's friendship with his classmate Rowley is temporarily destroyed by the jealousy of Greg's girlfriend and Rowley's girlfriend, Abigail Brown.

A large part of the series centres on the bizarre and unpredictable children Greg tries desperately to avoid, with Frigley being the most prominent of these. He is a highly eccentric neighbour with no sense of personal boundaries who becomes uncontrollably frenetic when exposed to sugar. Albert Sandy is known to be a boy who spreads totally illogical and absurd rumours, and Ruby Bird, a girl notorious for biting people when she gets upset. The books also describe even more extreme outcasts, like the feral Mingo kids who live in the woods and attack anyone who comes near their camp, or Evelyn Trimble, who genuinely believes she is a vampire. These characters basically exist to make Greg's daily life as uncomfortable and chaotic as possible.

The rest of Greg's peers mainly serve to support specific jokes or school events. For example, Darren Walsh and Abe Hall are known for starting the infamous "Cheese Touch" game that drives the plot of the first book. Chirag Gupta is a kind kid who becomes the target of a huge school prank where everyone pretends he is invisible. Others, like Collin Lee, act as temporary plot devices, with Collin briefly stepping in as Rowley's best friend. There are also familiar faces like the Snellas, a family with many boys whose half-birthday parties Greg hates, adding to the frustrating environment Greg has to deal with.

The series features various teenagers and adults who create challenges for Greg and his family. For example, Bill Walter is a 35-year-old unemployed musician that Rodrick admires, which frustrates Frank. Bill serves as a cautionary tale of what Rodrick might become if he doesn't pay attention to his future. Greg also frequently encounters aggressive bullies like Pete Hosey, a hostile teen who harasses him on Halloween, and vacation nuisances like the Beardos, a loud family that consistently wrecks the Heffleys' road trip in The Long Haul. Even younger kids act as antagonists, such as Taylor Pringle, a highly aggressive little girl who goes out of her way to embarrass and physically attack Greg in the live-action films.

At school and in the neighborhood, authority figures and rival families increase the pressure Greg and his dad experience. Frank Heffley is deeply insecure about the Warrens, a highly athletic and successful family that constantly makes Frank want to force Greg into being more masculine. At school, Greg faces tired, cynical staff members, including his resentful history teacher, Mr. Huff, and the school's corrupt founder, Larry Mack Sr., who secretly stole school funds to open car dealerships. Meanwhile, characters like Lenwood Heath—a former teen delinquent who turns his life around after being sent to a strict military academy—are often used by Frank as a threat to send Greg away whenever he misbehaves.

The books also make fun of the media, internet culture, and folklore that middle schoolers love. A big recurring joke is Rowley's blind loyalty to Joshie, a European pop singer clearly aimed at young kids and girls. On the other hand, Rodrick is obsessed with the aging and dysfunctional members of the heavy metal band Metallichihuahua, whose failed careers, petty rivalries, and legal issues are heavily discussed in Diper Överlöde. The series explores internet fame through characters like Mac Digby, a parody of loud YouTube gamers, and delves into childhood superstitions with Silas Scratch, a made-up campfire legend created by Frank years ago to keep other campers away from a comfy maintenance shed.

Finally, the Heffleys' town has many one-note characters and neighbourhood extras who exist to make Greg's life a bit more awkward. This includes kids like Scotty Douglas, a silly first-grader who looks just like Greg's awful comic strip drawings, or classmates defined by a single embarrassing incident, like Cody "Dookie" Johnson. From grumpy neighbours who refuse to pay for yard work to random background names like the extremely competitive Woodley brothers, these minor characters add to the chaotic, slightly absurd world of Greg's hometown. They usually appear just long enough to deliver a quick joke or accidentally foil one of Greg's selfish plans.

The various pets in the series often highlight the Heffley family's dysfunction or serve as jokes in ongoing gags. For instance, Sweetie is a dog that Frank buys because he feels guilty about his childhood pet Nutty. However, Sweetie’s demanding behavior and laziness eventually cause the family to give him to Gramma. Similarly, the pet pig that Manny wins adds a touch of absurdity to the later books, as it shows human-like intelligence that often frustrates Greg. Other animals, like the brothers' briefly owned fish or Aunt Veronica’s famous dog Dazzle on social media, highlight the differences between Greg and his siblings or poke fun at modern trends like influencer culture. These pets aren’t shown as typical companions, and they primarily act as sources of chaos that disrupt the family’s daily life and expose the character flaws of the people around them.