Parvomay Municipality (Bulgarian: Община Първомай) is a municipality in Plovdiv Province, Bulgaria, with administrative center Parvomay.
Parvomay Municipality is situated in the most Eastern area of the Plovdiv field – part of the Upper Thracian Plain, with total area of 864 m2. The Municipality encompasses 17 settlements with population in 2008 of 32 131 people. falling in 25,600 in 2011.
Two rivers run through its territory – the Maritsa river and the Mechka river. Valuable water resource are the thermal mineral springs in Dragoinovo, Biala Reka and Lenovo. The surroundings of Vinitsa village is the unique place in Bulgaria where Leucojum is to be found in the wild. The municipal center – Parvomay is situated at 134 meters above sea level. The surface of Municipality Parvomay is predominantly plain. Exceptions are the fields of the villages Voden and Bukovo and partially – those of Iskra, Briagovo, Dragoinovo and Ezerovo, which are situated in the frontier mountain Dragoina – part of the Rhodope Mountains, passing to the South-West into the Novakovski Balkan (mountain). The soils are predominantly black humus. There are also vast areas of cinnamon-forest type. In the lowland of the Maritsa river there are meadow–cinnamon soils. Meadow–alluvial soils are also to be found (the most fertile ones), as well as meadow–marsh ones. The territory of Municipality Parvomay belongs to the area of transitive Mediterranean climate. The average temperature in January is 1˚С, and about 25˚ С in July. The summer is dry and hot and the winter is comparatively mild. The snowfall is thin and not durable. The total precipitation is below the average for the country, about 532 l/m². The precipitation is highest in December and May and lowest in August and February–March. The relative humidity is particularly low – up to 60%. The strongest wind comes from the North-West, mainly in May and June, when it blows for weeks with average velocity of about 3 m/s. Thunderstorms and hailstorms are quite common in summer. Fogs happen along the Maritsa river but they are not common.
In 2011, over 200,000 photovoltaic panels were constructed near to the village of Karadzhalovo to the east of Parvomay town to form, Karadzhalovo Solar Park.