The surname Ossowski (singular masculine), Ossowska (singular feminine), or Ossowscy (plural) (also Osowski / Osowska / Osowscy) belongs to a Polish noble family. The name derives from the Polish place-name Ossowy, with the suffix -ski indicating land-ownership or lordship. Variants of the name include Ossowskiego, Ossowskich, and Ossowskliéj; the German or Prussian equivalent sometimes appears as von Ossowski. The family originally belonged to the clan Do ga but began to use the present surname in the 14th or 15th century.