Based on the cycle process of the tidal force of celestial body and the Outgoing Longwave Radiation (OLR) data，we analyzed the relationship between the tide force and infrared abnormal changes before and after 4 earthquakes that occurred at the regions of Yunnan and Tibet of China． The images of the daily increment of OLR by choosing the minimum of the tidal force period approaching the earthquake as reference background，and subtracted it from the surface OLR with day by day，same time and same scope，showed that the infrared anomalies were obvious near the epicenter，the anomaly expansion were controlled by the fault structure，and the anomaly distribution is closely related with fracture; the process of anomaly evolution was as follow: Initial infrared rise—enhancement—reaching peak—attenuation—re-enhancement— earthquake occurred—return to baseline． It was consistent with the regulation of rock broken procession under stress load． It implied that the evolution process of the critical condition of crustal stress can be reflected through changing of OLR radiation and the tidal force plays as an inducement role for changing the accumulate-unbalance of the structure internal crustal stress．