Prem Yog is a romantic comedy drama. The movie revolves around a prince named Raju (Rishi Kapoor), the son of the king Maharaj Chatrapal Singh. On his birth, the royal priest predicted that Raju would get no throne and Maharaj Chatrapal would be the last king of his lineage. Thus, to protect his son, Maharaj makes Raju to live a secluded life within the four walls. When Raju grows up, his marriage is arranged to a girl with a royal lineage, but he is not happy with this arrangement. Thus, Raju runs away to Bombay, with the help of his bodyguard. In Bombay, he starts to work as a waiter and falls in love with a beautiful girl named Anita (Madhoo). The two have a good time together. However, what will happen when Anita learns the truth?