Postołowo is a village in the administrative district of Gmina Trąbki Wielkie, within Gdańsk County, Pomeranian Voivodeship, in northern Poland. It lies approximately 7 km south-west of Trąbki Wielkie, 19 km south-west of Pruszcz Gdański, and 29 km south-west of the regional capital Gdańsk. It is located within the historic region of Pomerania. Postołowo was a royal village of the Polish Crown, administratively located in the Tczew County in the Pomeranian Voivodeship.