Based on comparing DST (Dempster-Shafer Theory) with DSmT (Dezert-Smarandache Theory), propose a information-fusion method which combined DST with DSmT. Use tests to analyze and compare two theories, aiming at the paradox between complex calculation process and reasonable calculation result, combine two theories and carry out algorithm simulation. The simulation result shows that the method is efficient enough to deal with conflict information and distribution precision and calculation at the same time.