This master's thesis present design of heating, cooling and ventilation systems for pharmaceutical production building with a total usable floor area of 2000 m2. The pharmaceutical production building is located in the city of Zagreb. Building has offices, storage facility, underground garage and laboratories for pharmaceutical production. Medicinal production is carried out in acceptable design and strictly controled ''cleanrooms'' which basic function is to protect the manufactured product from contamination. Office rooms and warehouses HVAC system is carried out as an air-water system with two pipes fan coil elements as heating or cooling bodies and a central air conditioning unit for ventilation air preparation. Hot water is used as a heating medium in a 70/55 ° C regime, and as a cooling medium is used solution of ethylene glycol with a 30% weight ratio and a 7/12 ° C regime. Medicinal production sites demand large amounts of clean filtered air. To maintain comfort and air quality, an central air conditioning system with 100% outdoor air and heat recovery from exhausted air is provided. The air conditioning unit is located on the flat roof of the building. Gas condensing boiler and water cooler with the air-cooled condenser were selected for heating and cooling. Ventilation of the underground garage and sanitary rooms was solved with two separate ventilation systems. Calculations of the thermal losses according to the EN12831 and the thermal gains according to VDI 2078 were performed in first part of this master’s thesis. These calculations were used for proper dimensioning and selection of system components. At the end of the thesis there is an overview of the technical drawings which define the layout of the system components and their regulation schemes.