Paul Siefert (23 May 1586 – 6 May 1666) was a German composer and organist associated with the North German school. Born in Danzig (Gdańsk), Royal Prussia, he was the son of a procurator and was named after his father. Siefert studied with Jan Pieterszoon Sweelinck in Amsterdam from 1607 to 1610, supported by a scholarship from the Danzig city council. After his studies, he returned to Danzig and became the assistant organist of the Marienkirche. Despite his aspirations, he failed to secure the position of principal organist due to criticisms of his arrogance and performance style.

In 1611, Siefert moved to Königsberg to become the organist of Altstadt Church and later served as the court organist in Warsaw starting in 1616. He returned to Danzig in 1623 as the principal organist of the Marienkirche, a position he held until his death. Siefert's career was marked by disputes, notably with Kaspar Förster and Marco Scacchi, and he faced challenges at the Warsaw court.

Siefert was a prolific composer, known for his vocal and instrumental works, including settings of psalms and chorale variations. His compositions often reflected the influence of his teacher Sweelinck, though they were not always highly regarded. His theoretical work includes "Anticribratio musica ad avenam Schachianam" (1645). Despite his contentious relationships, Siefert's legacy includes contributions to the development of the concertato chorale motet and the chorale cantata.