National Institute of Meteorology and Hydrology
- Gives for more than 134 years its humble information and scientific contribution to the mastering and studying of the problems related to the climate change, weather and water resources.
- http://www.meteo.bg/

Geophysical Institute
- Conducts research in the fields of seismology, geomagnetism, gravimetry, physics of the atmosphere, ionosphere and geospace.
- http://www.geophys.bas.bg/

Geological Institute
- Performs principal geological science research, includes brief history, departments, research, and periodicals.
- http://www.geology.bas.bg/