In this study, we were using three variants of tomato plants to characterize the recent Fusarium isolates collected from Taiwan, which is Bonny Best as our susceptible check, UC-82L that have I-1 resistance gene that makes them resistance towards race 1, and MH-1 that I-1 and I-2 resistance gene that makes them resistance towards race 1 and race 2 isolates. In this experiment, we divide the experiment into two parts bioassay and phenotyping, where for the bioassay using root dip technique for the inoculation of the pathogens, as for the phenotyping we use several primers to identify Fusarium oxysporum specific and determine the races of FOL isolates. With the help of NCBI BLAST, we can identify other several fusarium isolates.