The Gremlin Rag is the main theme song of the two movies. It was composed by Jerry Goldsmith. The theme of the music song is to beware of the Gremlins, as the music is played in a horror theme. It was played at most full length at the end of the first film, just after Randall Peltzer (played by Hoyt Axton) says, "Well, that's the story. So if your air conditioner goes on the fritz, or your washing machine blows up or your video recorder conks out, before you call the repairman, turn on all the lights, check all the closets and covers, look under all the beds, cause you never can tell... there just might be a Gremlin in your house."
This is one of the six songs composed by Jerry Goldsmith who made one of these into the film's soundtrack and it has also been used for the OETA Movie Club with BJ Wexler. The second film, The New Batch, had a edited version of the song.