The brother of Gonta and a kaiju.
Gorizaemon (ゴリザエモン) is a gorilla Kaijuu whose speciality is making his nose drip on command. Kinnikuman hires him to kidnap pop idol Nana Takahara so Kinnikuman can save her and win her over, but he falls for Nana and fights back. Kinnikuman eventually defeats him. He has a sister named Gonta.
In an attempt to woo Nana Takahara, Kinnikuman hires the kaiju named Gorizaemon to stage a kidnapping, so that he may 'save' Nana and amaze her in the process.  Gorizaemon appears even before Kinnikuman has made the phone call, and Kinnikuman hands him a script to follow for the entire process of the kidnap attempt. He hires him for 500 yen (the same fee that he later gives to Gonta for similar services). 
Gorizaemon attempts to scare Nana, but - as she is so 'cute' - he dislikes being beaten up in front of her, so he starts to attack Kinnikuman back in response. Gorizaemon carries Nana onto a nearby building, in a style similar to 'Godzilla'. Kinnikuman is eventually able to overcome Gorizaemon, and catch Nana from her fall at the large height. Hitoshi attacks Gorizaemon while he is unconscious, which leads Nana to believe that Hitoshi saved her from the attack.