Buire-le-Sec (French pronunciation: [bɥiʁ lə sɛk]; Picard: Buire-l'Sé) is a commune in the Pas-de-Calais department in the Hauts-de-France region in northern France.

Buire-le-Sec is a village situated some 5 miles (8 km) southeast of Montreuil-sur-Mer on the D139 road.

Historical population

Year	Pop.	±% p.a.
1968	604	—
1975	543	−1.51%
1982	551	+0.21%
1990	663	+2.34%
1999	788	+1.94%
2009	793	+0.06%
2014	793	+0.00%
2020	759	−0.73%
Source: INSEE

The church is one of the most beautiful and oldest in the arrondissement of Montreuil. It was built in the 12th century, though all that remains of that church are the foundations. Some 13th century features remain, but mostly it is of 16th century construction (the nave and transept). It is in the form of a Latin cross and built from chalk. The dimensions are: 32 meters long, including 19m for the nave and 7m for the choir. The width of the choir and the nave is 6m, the transept 15.50m in total. The porch has ribbed vaulting.

• Communes of the Pas-de-Calais department

• Buire-le-sec website Archived 11 February 2008 at the Wayback Machine