Under the background of global warming, the Record-Breaking Event (RBE) of high temperature occurs more frequently and attracts the worldwide attention. This paper analyzed the variation of the RBE of high temperature in recent years and estimated the possible variation under different warming scenarios in the future based on a coupled model (BCC_CSM1.1) developed by national climate center. The daily maximum temperature simulation data on a single point showed a normal distribution, and the RBE of high temperature is in line with the stochastic theory. On this basis, we compare the simulation and theory of RBE of high temperature in the northern hemisphere in recent 50 years. The results show that the ratio between simulation and theoretical value takes a significant rising trend and varies in different regions, namely, the ratio is higher in ocean than in land, and higher in low-latitudes than in mid-latitudes. Through the correlation analysis of temperature, it is learned that the rise of temperature in the northern hemisphere plays the primary role in the rising trend of the ratio of RBE of high temperature. Moreover, the variation characteristics of RBE frequency of high temperature under two warming scenarios (RCP4.5 and RCP8.5) were compared. The large difference is found in the later half period (2060—2098), with the ratio significantly rising under RCP8.5 while stable under RCP4.5. Such difference is the response to the changes of temperature, and this response of the low-latitude ocean is more sensitive than that in land.