Throughout the 18th century, the history of the opera has changed and the influence of opera on the audience was profound and frequent, especially in France and Holy Roman Empire. In the early 18th century, the content of operas became increasingly weak, and it was divorced from the meaning of drama since it became the carrier of national propaganda, most of which served the upper classes and nobles. This kind of opera that promoted autocracy slowly caused dissatisfaction in the audience, as a reaction, the content of opera began to promote independence, freedom, and love. In both countries, this had a more positive impact on the audience who began to desire independence, freedom, and equality. It also had an effect on political movements and historical events. This study will be divided into three main sections. It will first indicate the history of opera and the influence of opera on the audience in the 18th century in France. Secondly, it will examine the history of opera and the influence of opera on the audience in the late 18th century in Holy Roman Empire. Finally, some conclusions will be drawn, in the late 18th century, both the French and Italian operas changed and the influences on the audience changed.