The sound of Vigo growling is exactly the same growl that the terror dogs from the first Ghostbusters make.

Viggo was based on Vlad the Impaler, the medieval Romanian tyrant who was also the inspiration for Dracula.

When Ray and Egon see Vigo's name on the "Occult Reference Net," his last name is the same as the twin actors who play Oscar.

This is the only sequel that Bill Murray has ever appeared in. Apparently, he doesn't like sequels, as at one point in the production of this movie, he wanted the title to be, "The Last of the Ghostbusters."

Slimer had no name in the first Ghostbusters movie, but the producers nicknamed him "onionhead" because of his awful smell. He was named Slimer in the cartoon series "The Real Ghostbusters." The name came from the scene in Ghostbusters where Ray shows Winston the containment unit and says, "This is where we store all the vapors and entities and slimers we trap." Since Venkman was slimed in the hotel, they decided to name the ghost that did it Slimer.

The baby who plays Oscar is twins, played by Hank and Will Deutschendorf. These boys are the nephews of the late singer John Denver (formerly Deutschendorf). The boys are John's brother Ron's children.

The original theatrical version ended with Slimer eating the camera, just like in the first Ghostbusters film. This has been removed for the video releases.

At the beginning of the film, when Ray and Winston are at the children's party, the kid that says they're full of crap is Ivan Reitman's son, Jason. The girl with the puppy at Egon's institute is Ivan Reitman's daughter, Catherine.