Abstract:315 field samples of processing tomato showing necrotic stripe symptom were tested for virus by ELISA using monoclonal antibodies(MAbs)against Tomato mosaic virus(ToMV),Broad bean wilt virus(BBWV)and Cucumber mosaic virus(CMV),respectively.The result showed that the invading rate of ToMV,BBWV and CMV was 69.3 %,66.7 % and 75.1 %,but sole infection rate of these 3 viruses was only 1.5 %,2.4 % and 8.5 %,respectively.These indicated that the mixed infection was probably the main cause to induce necrotic stripe disease in Shihezi area.Situation of the above mentioned 3 viruses carried by 21 processing tomato cultivars were tested by ELISA.The result showed there existed definite differences in resistance among cultivars,although all tested cultivars had relatively high amount of viruses.