Peanut stripe virus was detected in soybean in all of the major production areas of Taiwan, where it seems to occur at least as frequently as soybean mosaic virus. Several lines of the AVRDC soybean germplasm collection and of locally grown soybean cultivars were immune to this virus. Significant yield reductions of up to 90% occurred in susceptible cultivars. The 100‐seed weight was reduced by up to 50%. Seeds of plants artificially inoculated with the virus up to the R1 stage were abnormally discoloured. A low percentage of seed transmission (2%) was observed only in seeds collected from one of three cultivars ofGlycine max(KS‐8) which had been inoculated at the earliest (V‐1) stage of growth.