Infrasound　has　been　widely　used　for　observation　of　associated　events　such　as　earthquakes　and　volcanic　eruptions,　etc.　The　relatively　low　acoustic　attenuation　allows　infrasound　to　transmit　for　a　long　distance　from　sources　to　propagate　in　the　atmosphere　at　frequencies　between　1　and　20　Hz　and　to　be　recorded　regionally　or　globally.　In　addition,　numerous　data　telemetered　from　the　booming　global　networks　of　infrasound　stations　supply　us　a　better　understanding　of　the　infrasound　generation　mechanism　and　remote　effects　of　earthquakes.　Recent　efforts　in　source　identification　focus　on　the　calculation　methods　of　infrasonic　data,　considering　propagation　conditions　including　profiles　of　sound　velocity　and　wind　speed　in　the　higher　atmosphere.　In　turn,　we　can　validate　atmospheric　model.　In　this　paper,　we　place　attention　to　several　plausible　generation　mechanisms　of　distinct　infrasound　from　earthquakes　of　different　magnitudes,　as　well　as　the　merits　of　infrasound　arrays.　Some　detailed　case　studies　are　given　at　the　end.　On　the　basis　of　these　studies,　we　will　propose　some　feasible　measures　in　future.　It　is　no　doubt　that　infrasound　research　will　be　an　active　field　either　for　precursory　earthquake　infrasound　or　for　co-,　post-earthquake　infrasound.