Jan Baptist van Deynum, Dynen or Duinen (1620–1668), was a Flemish Baroque painter and a captain of the local civil guard in Antwerp.

He may have been a member of the family of artists active in Antwerp, which included the still life painter G. van Deynum and the staffage painter Abraham van Deynum.

The contemporary Flemish artist biographer Cornelis de Bie praises Jan Baptist van Deynum in his Het Gulden Cabinet of 1662 as a respected painter who neglected his job as captain of a local civil guard in Antwerp in order to have more time to pursue his passion for painting.

[1] According to the text below his portrait in de Bie's Het Gulden Cabinet, van Deynum painted portraits, landscapes and other miniature figures.

[3] This appears to suggest that van Deynum mainly painted decorative works and cabinet paintings and can explain why no surviving works are currently attributed to him.