Anechoic room is a special laboratory for acoustics testing. It is widely applied for the testing of acoustic properties of electroacoustic products and for the measurement of the sound power levels of noise sources. In the design of anechoic room, the acoustic principle should be obeyed, the requirement of application, the acoustic environment and the cost of construction should be considered. Taking an anechoic room construction as an example, some technical problems such as volume, type, sound absorption, sound insulation etc are discussed. An acoustic measurement is carried out after the anechoic room was completed. The measurement data shows that all the acoustic indexes are satisfactory or even better than those given in national standard.