For the purpose of noise control, the sources and mechanism of the HVAC (Heating Ventilation and Air Conditioning) system noise on offshore platform were analyzed. It is shown that besides the HVAC system noise there are ambient noise and the secondary noise radiated by piping system, and based on the theory of noise control, the measures of noise reduction were proposed. Results of this research provide some reference for noise control of offshore platform HVAC system, and also have a guiding significance for HVAC system design in the field of marine engineering.