Boecillo is a municipality in Spain, located in the province of Valladolid within the autonomous community of Castile and León. It lies in the northern part of the country's interior, in the region traditionally known as Old Castile.
According to the 2025 census conducted by Spain's National Statistics Institute (INE), the municipality has a population of 4,446 inhabitants. This figure places Boecillo among the smaller municipalities of the province, which is centred on the city of Valladolid.
As a municipality, Boecillo constitutes a basic unit of local administration in Spain, with its own local government responsible for the day-to-day running of the area. The town is situated within the broader comarca surrounding Valladolid, the provincial capital and largest city of the province.