Theater Aachen is a theatre in Aachen, Germany. It is the principal venue in that city for operas, musical theatre and plays. It is the home of the Sinfonieorchester Aachen. The original project was by Johann Peter Cremer, later altered by Karl Friedrich Schinkel. Construction on the original theatre began in 1822 and it opened on 15 May 1825. A bomb attack on 14 July 1943 destroyed the first theatre, and the current structure was inaugurated on 23 December 1951 with a performance of Richard Wagner's Die Meistersinger von Nürnberg.
The conductors of the theatre have also been Generalmusikdirektor of Aachen: