Miastkowo [mjastˈkɔvɔ] is a village in Łomża County, Podlaskie Voivodeship, in north-eastern Poland.

[2] A church and parish were founded in 1451 by Dukes from the Masovian line of the Polish Piast dynasty.

[3] During World War II, the settlement was occupied by the Soviet Union from 1939 to 1941, and by Nazi Germany from 1941 to 1944.

The Germans operated a penal forced labour camp in the village.

[5] During the Holocaust, local Pole Józef Dąbkowski managed to hide and rescue nine Jews from the Germans.