Are there classes in Dragon Quest V?

Answer 1

Yes and no, playable characters in DQV mostly adhere to a class based system, but never get the option to change. Your main character will always be primarily a warrior with some support spells, for example. If you recruit a Prestidigitator, it will always be a wizard, with damage-dealing spells and limited armour and weapon options. So you build a balanced party using different monster types.