W.F. Bach's musical instruction was primarily from his father (who wrote for him, when he was ten, the charming Klavier-büchlein vor Wilhelm Friedemann Bach of keyboard pieces). He also studied the violin. He matriculated at Leipzig University in 1729. In 1733, already composing extensively, he was appointed organist to the Church of St. Sophia in Dresden. In 1746 he moved to the Liebfrauenkirche at Halle. At about this time, or perhaps later, after his father's death in 1750, he seemed to begin to have personality difficulties, evidenced by excessive drinking and other lapses. After a late marriage in 1751, he became restless and applied unsuccessfully for a change of post in 1753 and 1758. In 1762 he won an appointment to the Darmstadt court but did not take it up. Resigning his old post in Halle in 1764, for 20 years he sought in vain for regular employment. He became touchy and unreliable, and although his talents were never doubted, he imagined that they were. In 1774 he moved to Berlin, where he lived meagrely by giving recitals and teaching.

Of his compositions, keyboard works and cantatas form the larger part; he also composed several symphonies and chamber works and an opera. His music vacillated between the Baroque style of his father and the newer galant, or Rococo, style. His compositions, few for his many years, are often impassioned, often unpredictable in their use of melody, harmony, and rhythm.