Abstract: We constructed a matrix decision-making algorithm (MDA) for discriminating explosions from earthquakes. In order to meet the need of quickly identifying explosions and earthquakes, we examined 5 criteria, among which the first motion polarity and amplitude ratio criterion are better in use for the discrimination. Using MDA method we identified and tested 62 seismic events in Beijing region and its vicinity. The rate of correct recognition reaches to 97% for C test and 93% for U test with 5 criteria. Choosing any 4 of the 5 criteria in turn we made 10 recognition tests, 7 of the 10 test results gave the correct recognition rates above 93%. These results show that the MDA algorithm we constructed is effective in discriminating explosions from earthquakes and can be applied to quick recognition of seismic events.