Using NASA official website downloading OLR primary datum, processing for two-dimensional space datum and simple point time-sequence datum, since through the earthquake table of contents checking contrast, using the OLR monthly mean field method and OLR monthly mean field anomaly method ,has analyzed Inner Mongolia and the peripheral locality (N35°-55°, E95°-130°) before 337 earthquake events (Ms≥5), long-wave radiation space and time change characteristic since 1974.Discovery: in front of earthquake 3~5 months, long-wave radiation (OLR) all appeared the obvious exceptionally change before many earthquakes; Many positions are exceptionally also obvious in front of earthquake.