Pirin Macedonia (Bulgarian: Пиринска Македония, Pirinska Makedonia) is the smallest part of the geographical region Macedonia located on the Balkan Peninsula, today in southwestern Bulgaria. This region coincides with the borders of the Blagoevgrad Oblast, adding the surrounding area of the Barakovo village from the Kyustendil Province. After World War I, Strumica and the surrounding area were broken away from the region and were ceded to Yugoslavia.
It covers an area of about 6,798 km2 which is 10.18% of the geographical region Macedonia. One of the regional centers is Blagoevgrad, also known as Gorna Dzumaya, the old name of the city. The region is bordering with Kyustendil Province and Sofia Province on the north, Pazardzhik Province and Smolyan Province on the east, Greece on the south and North Macedonia on the west. The population is estimated around 325.000 people.
The name of this region comes from the Pirin Mountains which are spread in the central part of Pirin Macedonia. The mountain name Pirin comes from Perun (Bulgarian: Перун), the highest god of the Slavic pantheon and the god of thunder and lightning. In the antiquity the range was called Orbelos by the Thracians, meaning "snow-white mountain" in Thracian language.
It usually refers to the part of the region of Macedonia attributed to the Kingdom of Bulgaria by the Treaty of Bucharest (1913). Until World War I, in the region were included the areas present-day Strumica and Novo Selo Municipality, today in North Macedonia. After World War I, they were broken away from Bulgaria and ceded to Kingdom of Yugoslavia.