The invention provides an apparatus for testing flame propagation and flame suppression in the flammable gas and air premixed gas explosion process. The whole apparatus comprises a combustion pipeline, a water mist generating device, a metal net fire retardance device, a high-speed camera, a schlieren system, a pressure testing system, an automatic gas distribution system, a temperature testing system, an ion probe detection system, a data acquisition instrument, a high-tension ignition system and a synchronous controller. Through the apparatus, flame propagation characteristics and flame propagation rules are researched in the premixed gas explosion process under the influences of factors such as different flammable gas components, different opening states, different ignition positions and different types of flame instability, the effects of stopping agents, fire-retardant metal nets, water mist and the like on controlling and restraining flame propagation are researched, a method and technology for restraining premixed gas flame propagation are developed under the physical-chemical coupling effect, and the inner mechanism of the apparatus is explained.