Hiller was a teacher who encouraged musical education for women, his pupils including Elisabeth Mara and Corona Schröter.
In 1751, he enrolled in Leipzig University to study law, supporting himself by giving music lessons, and also by performing at concerts both on the flute and as a singer.
During that time he wrote several symphonies, church cantatas, and arias, as well as a fragmentary Singspiel entitled Das Orackle.
To Hiller has been given the credit of being the originator of the Singspiel, the beginning of German comedy opera as distinct from the French and Italian developments.
Among his sacred compositions are: A Passion Cantata, Funeral Music in Honor of Hasse, a setting of the one hundredth Psalm; and a few symphonies.
Since he no longer had any occupation in Leipzig he had to organize concerts to earn his living, but fortunately he was able to secure for himself the post of music director of the city of Breslau in 1787.
He spent two years in Breslau and returned to Leipzig in 1789 to become cantor at the Thomaskirche, conducting the Thomanerchor, a position filled by Johann Sebastian Bach before.
In addition, Hiller carried out notable work as an editor and publisher of other composers' output, and wrote considerably concerning musical topics.
Writings of Hiller on aesthetic issues include the Abhandlung über die Nachahmung der Natur in der Musik (1754) and Über die Musik und deren Wirkungen (1781), which is a translation from Michel Paul Guy de Chabanon’s Observations sur la musique.
In these publications Hiller presents himself as a highly competent teacher who regarded knowledge of music an essential part of everyone's education.