When Bach was twenty-two years old, he married his cousin Maria and gave birth to seven children. After Maria's death, Bach married the female singer Anna Magdalena. Thirteen more children were born. Nine of Bach's children grew up, and three of them inherited their father's business and became very influential musicians.

His third son, Karl Philipp Bach (K.P.E.Bach), has lived in Hamburg for a long time and is known as "Hamburg Bach"; his seventh son, Johann Christian Bach (J.C.Bach) ) has lived in London for a long time and is known as the "London Bach". They all have a status in the history of music and have a direct influence on Haydn, Beethoven, etc.

Musical families like Bach are rare in history and have always been an unsolved mystery in medicine and genetics.

The Bach family can undoubtedly be called a musical family. According to the "Bach Family" entry in the authoritative "New Grove Dictionary of Music and Musicians", this family spans seven generations from Bach's great ancestor to his grandson. After more than 260 years, many people are engaged in the music industry. There are 78 people, 14 of them are outstanding, and the most outstanding one is of course Johann Sebastian Bach.

In the history of European music, there are many musical families that are passed down from father to son, brother or son-in-law, such as the Purcell family in England and the Scarlatti family in Italy; but among these families, only the Couperin family in France (There were five generations of musicians from the 17th to the 19th century, of which Francois Couperin was the most famous) or it may be comparable to it.

Bach’s family can be considered prosperous. He himself had 20 children, but only half lived to adulthood. After Bach's death, his sons and disciples were still active in the European music scene. Among them, the most accomplished ones were the second son Carl-Philip Emmanuel and the youngest son John Christian, who became important musicians in the early classical period. . But the good times did not last long, as no male descendant of his family survived the second generation. In 1843, Bach’s last grandson (who was already over 80 years old at the time) attended the unveiling ceremony of the Bach monument donated by Mendelssohn. He died two years later, and the Bach family, which has been famous in the music world since then, has no successor.