Straldja municipality is located in the eastern undulating section of the Thracian lowlands, the rolling areas of the Tundja River valley. The most northerly parts reach to the foothills of the Balkan Mountains while the southernmost point goes to the slopes of the Bacadjitsite Mountain rise and the northwestern spur of the Straldja Mountain. In the north, the municipality borders on Kotel municipality; in the east, the municipalities of Karnobat and Sredets; in the south, Bolyarovo and Elhovo municipalities; and in the west, Tundja municipality and the town of Sliven.
Total area for the municipality is 722 square kilometers, with 81% in agriculture. Straldja municipality is a traditional agricultural area with an ancient past.
There are 21 villages and one town wich is administrative center of the municipality - town of Straldja, situated in the northern portion of the municipality.
Cities and villages in Straldja municipality: Village of Aleksandrovo, Village of Atolovo, Village of Bogorovo, Village of Charda, Village of Djinot, Village of Irechekovo, Village of Kamenets, Village of Leyarovo, Village of Lozenets, Village of Lyulin, Village of Malenovo, Village of Nedyalsko, Village of Palauzovo, Village of Polyana, Village of Pravdino, Village of Purvenets, Village of Saransko, Town of Straldja, Village of Tamarino, Village of Vodenichane, Village of Voynika, Village of Zimnitsa