Abraham Willemsens or Abraham Willemsen, was a Flemish painter of history and genre paintings. His genre scenes were reminiscent of the style of the Le Nain brothers. He also produced copies after the works of Rubens.

Details about his early life such as his birth date and place are unknown. In 1627-1628 he is recorded in the Antwerp Guild of Saint Luke as a pupil of Gilliam Antonissens (also called Guillaume Anthoni), a French painter active in Antwerp. Willemsens married Maria de Lang. In 1645, he was elected dean of the Guild. He was recorded in Paris the same year.

It is assumed that he operated a big workshop with a large output to supply the export market. As a result, a large number of his paintings can be found in Spain. He was recorded in the archives of the prominent Antwerp art dealer Guillam Forchondt in 1669 and also worked for the art dealer Matthijs Musson. He was active as an art dealer himself. He had two apprentices, respectively in the years 1651/52 and in 1654/55.

He died in Antwerp.