Abstract: In this paper , vicia faba roof tip cells are attended by ext ract s of spirulina platensis in different concent ration alcohol , following , poison t readed by towin20 , to observe the rest rain of micronucleus effect s of vicia faba roof tip cells on towin20 , by ext ract s of spirulina platensis. From the angle of micronucleus effect s of vicia faba roof tip cell , by statistical analysis : The positive cont rol of poison t readed by towin20 compared with the negative cont rol P < 0. 01 ; Poison t readed by towin20 after attended by ext ract s of spirulina platensis in best concent ration alcohol compared with the positive cont rol P < 0. 01. Result showed that towin20 is a st rong mutagen to cause significant micronucleus effect s. But , the ext ract s of spirulina platensis has significant rest rain to micronucleus effect s of vicia faba root tip cell on towin20 . Further more , approach the function of spirulina platensis to prevent cancer on the original of oncology on cell level. In the mean time , this experiment has tentatively gained a simpler and easier method to ext ract the effective composition of spirulina platensis.

Key words: spirulina platensis, towin20, micronucleus of vicia faba root tip cell