Tōru Kazama is Shin-chan's immaculately groomed and perfectly mannered friend, who usually loses his mind when Shin-chan teases him, among other things. He also bickers and fights with Shin-chan sometimes. Despite that, they are actually closer than any of the other friends they have. A strong evidence of this was when Kazama was extremely frustrated and lonely in several episodes, Shin-chan was the only one who stayed with him. Even though Kazama always denies it when Shin-chan says that he is his best friend, his best friend is Shin-chan, too. He participates in extracurricular activities like English Conversation and seems knowledgeable in any subject, which makes him appear as snobbish, but he is actually a good person. He plays association football and baseball very well. He likes female animation and comic book characters, though he tries to hide that fact from his friends. Since his father remains abroad for most of the year, he has a strong attachment to his mother, for which he is often ridiculed as a mama's boy. A recurring theme in the show is that he tries to hang out with upper class girls his age from his tuition classes to be a part of the "elite", but runs into Shin-chan being weird, which ultimately causes the girl to lose interest in hanging out with him. Another running gag is that whenever he tries to be serious while doing anything, Shinchan blows air into his ears  much to his irritation, causing him to lose focus & end up ruining the activity. 

Nene Sakurada (Nene-chan) is Shin-chan's female classmate and the only female best friend.. Her nickname is Nene-chan. She loves to play 'real omamagoto', or 'real house', which is basically a re-enactment of Japanese soap-operas in which divorces and arguments are very common and she typically forces her four male best friends to play with her this game exclusively over other games. This is always a nuisance to Shin-chan, Bo-chan, and Kazama-kun, and a nightmare to Masao as he often needs to be Nene's husband (unsuccessful salaryman) in the plot. However, she loves her friends very much and stands up for them without any hesitation. She occasionally sees her mother go crazy or do something out of character (usually it's because Shin-chan drives her crazy) and shrieks something which is literally translated to be "You're not my usual mom!" Nene styles herself as a sweet girl, but in fact she has inherited her mother's temper issues and is quite bossy. Like her mother, she hits a stuffed bunny to relieve her anger. She is the only female member of the Kasukabe Defence Force, and takes it very seriously. Despite her many flaws, she is a tough, headstrong and kind hearted little girl.

Masao Sato is a well-behaved but timid boy, often crying out of fright. Shin-chan and Nene sometimes tease him, but not in a bad way. Nene is often annoyed by his cowardice and encourages him to stand up for himself. Shin-chan and Nene often scold him  and make him cry while Kazama and Bo calm him down and comfort him. Even so, he is often shown to have a rebellious side when he gets driven. His nickname is "Onigiri" due to his shaven head's resemblance to a rice ball, and there are several moments where Shin-chan accidentally mistook Masao's head for a rice ball and even tried to eat it. Shin-chan often seeks out Masao in times of need. A running gag in the series is that Shin-chan often mistakes the house opposite to Masao's house as that of Masao. He seems to have a very low self esteem & is shown to break down into tears very often. He is a gifted artist whose hobby is to write and illustrate comics. He also likes to collect objects & maintains cleanliness hin-chan). He is also quite knowledgable and creative. Masao is in love with Ai-chan and jealous of Shin-chan because Ai-chan loves Shin-chan, but they are still best friends.

Another of Shin-chan's best friends, he seems slow and expressionless, but is actually quite smart and has an interest in artistic, adult-oriented things. He loves to collect various kinds of stone and investigating urban legends and various mysterious objects such as UFOs. He often surprises his best friends with his insight, though he speaks quite slowly. He always has a trail of mucus running down his nose and can perform various tricks with it. He is known as Boo in the Funimation dub, and he says he never wipes it away because he thinks that his snot is the source of his "power". He is portrayed as a stupid kid who often says nonsensical things like a sufferer from Tourette syndrome. He likes to collect pet rocks.