Augustin Reinhard Stricker (c. 1675 – between 1718 and 1723) was a German baroque composer, conductor and tenor singer. He was Johann Sebastian Bach's predecessor as Kapellmeister (music director) at the court of Leopold, Prince of Anhalt-Köthen and the dedicatee of Johann Mattheson's 1717 treatise Das beschützte Orchestre.
Little is known of Stricker's youth and personal life. The fact that he published a volume of Italian cantatas might indicate that, like most aspiring composers of the era, he probably spent considerable time studying in Italy. His first documented employment began in February 1702 when he was appointed to the post of Cammer-Musicus in the newly founded Hofkapelle (royal orchestra) of king Frederick I of Prussia in Berlin.
There, in 1705, he married the singer Catharina Elisabeth Müller, who would also be his professional partner for the remainder of his life; e.g., she also would be employed at the Köthen court. His first documented pasticcio, Sieg der Schönheit über die Helden (Triumph of Beauty over the Heroes), premiered at the Royal Prussian court in December 1706, clebratring the marriage of the crown prince, future king Frederick William I, and princess Sophia Dorothea of Hanover. While all the music is lost, the libretto, written by the Prussian Poet laureate Johann von Besser, indicates that Stricker wrote most of the music and also played the role of the god Neptune, so he probably had already earned a reputation as a capable singer and composer.
An opera entirely composed by Stricker, Alexanders und Roxanen Heyrath (The marriage of Alexander and Roxane), premiered in November 1708, celebrating Frederick I's marriage to princess Sophia Louise of Mecklenburg-Schwerin. Again, Besser wrote the libretto. Then 14-years-old Leopold of Anhalt-Köthen played a minor role. The young Georg Philipp Telemann, already a renowned composer in his own right, attended the representation, and Mattheson probably was in the audience, as well.