The Bolyarovo municipality is situated in one of the country`s regions with the most unpolluted environment. It is located in the south part of the Yambol district upon the north slopes of the Stranja Mountain. It encompasses a part of the Tounja Hilly Area, the Dervent elevations and the south slopes of Bakajitsite.
It encompasses an area of 667 sq. km and constitutes 0.06% of the Republic of Bulgaria`s territory. It borders the Republic of Turkey to south (55 km of common boundary), the Elhovo municipality to the west, the municipalities of Tounja, Yambol and Straldja to the north and the Burgas district - the Sredets municipality, to the east.
The relief in the Bolyarovo municipality is fairly varied. It consists of numerous elevations (hills and low mountains), among which spread the lightly indented and field lowlands of the Popovska River - a tributary to the Tounja River. The south slopes of the Bakajitsite overlap with the Dervent Elevations and reach an altitude of 556 m above sea level.