Abstract: By dynamic modeling based on Ross MacDonald's mathematical model, the characteristics of rapid transmission of malaria and slow transmission of filariasis was compared. The dynamic mechanism showed that the infection efficiency in filariasis, namely, the probability of becoming infected in man by one infective bite of mosquito, was much lower than that in malaria; hence the vectorial capacity or transmission velocity in filariasis was also markedly lower than that in malaria. Since the intensity of infection i. e. the microfilaria density can largely affect the infection efficiency in filariasis, drug treatment, especially using DEC -medicated salt can reduce the intensity of infection and the infection efficiency, thus interrupting transmission finally. However, for malaria, only when the measures for mosquito vector control (including mosquito proofing) are taken as a priority to reduce the vectorial capacity or transmission velocity, malaria can then be controlled subsequently. These theoretical analyses are being demonstrated by the practice for malaria and filariasis control in our country, which could also be used as a theoretical base for enlightening the successful filariasis control strategies in our country.