During the barley harvest in June 1990, there was a great deal of rainfall and high humidity in the southern part of Korea, and natural occurrence ofFusariummycotoxins was suspected in barley samples. The samples of undergrade barley were obtained from four provinces and analysed for the presence of deoxynivalenol (DON) and nivalenol (NIV) by gas chromatography and zearalenone (ZEN) by high performance liquid chromatography. Of 37 samples, 33, 37 and 10 were positive for DON, NIV and ZEN, respectively. The husked barley contained 29–677 ng/g for DON, 114–1546 ng/g for NIV and 183–1416 ng/g for ZEN. The naked barley contained 38–645 ng/g for DON, 85–4569 ng/g for NIV and 40–1081 ng/g for ZEN. The average concentration of NIV in naked barley was higher than that in husked barley, but the average concentration of DON in husked barley was higher than that in naked barley. The survey indicates that the 1990 barley crop in Korea was heavily contaminated withFusariummycotoxins.