In the paper, we briefly introduce the development and present situation of earthquake insurance in China and foreign countries, and the evaluation of earthquake losses on the basis of seismic risk and structural vulnerability analyses. The emphasis is given to the probabilistic density function of earthquake loss adjustment for a single building under the given insurance policy and the overall variance of estimated earthquake losses aggregated from various locations with keen interest in the insurance industries. The correlation coefficient for the damages among single structures in the United States is also introduced to interpret the risk of loss concentration in the earthquake insurance. The paper provides a scientific basis for adjusting earthquake loss and premium rate, and it also provides a useful reference for the application and expansion of earthquake insurance in China.