Portrait of Maria Pietersdochter Olycan is an oil-on-canvas painting by the Dutch Golden Age painter Frans Hals, painted in 1638, now in the São Paulo Museum of Art.

It is considered a pendant to the portrait of Maria's husband Andries van Hoorn.

Maria's younger sister Hester married the brewer Tyman Oosdorp.

On 25 July 1638 Maria married the widower Andries van Hoorn, also a brewer.

Andries survived his second wife by 22 years and lived to see his daughter Christine's wedding in 1657 to Adriaan Noirot, and his daughter Maria's wedding in 1662 to the diplomat jhr.

He also lived to see the Sypesteyn house be searched by a mob in 1672 on suspicion of hiding Johan de Witt, and though nothing was found, C.A.

van Sypesteyn continued to be mistrusted and was stabbed to death in 1673 in Gorinchem.

Maria van Hoorn outlived both her parents and her husband and died in 1704.

This portrait was documented by Hofstede de Groot in 1910, before the sitter was identified.

Purchased in the Isle of Wight, 1896, from the grandson of George IV.

[2]In 1974 Seymour Slive tried to trace the remark about the king's cook but there is no reference in the Royal collections of such a statement.

He remarked on Andries' portrait bearing an inscription and coat of arms while Maria's portrait lacks this, but notes that coats of arms were generally added by later descendants.