Svietlahorsk (Belarusian: Светлаго́рск, [sʲvʲetɫaˈɣorsk], until 1961 Šacilki, Belarusian: Шацілкі) is a town in the Svietlahorski Rajon of Нomiel'skaja Voblasс' of Belarus, the administrative center of the rajon (district). It is located by the river Biarezina and has 69,900 inhabitants (2010 estimate).
Within Svietlahorsk there are many industrial activities and organizations. They include: the power plant, a chemical man-made fiber plant, a reinforced concrete industrial complex, a Petroleum producing industry, a pulp and paper milk industry, butter-making factory, a bakery, and an industrial college.
Svietlahorsk is the region worst affected by HIV-AIDS in Belarus. Although the city accounts for less than 1% of the population of Belarus, it accounts for close to 30% of all the reported cases of HIV infections. Around 6% of the adult population in Svietlahоrsk is HIV +ve.