Carl August Thielo (February 7, 1707 – December 3, 1763) was a Danish composer. theatre entrepreneur, music teacher, organist from Saxony. He spent most of his life in Copenhagen from the 1720s onwards and founded the first opera house there in 1746.A student of Johann Gottfried Walther, he was the author of a Danish treatise, Tanker og Regler fra Grunden af om Musiken, published in 1746. Thielo was also the German court organist under Christian VI. He was the father of Caroline Thielo.