Eleven mycotoxins, including aflatoxins, ochratoxin A, fumonisins, zearalenone, T-2 toxin, deoxynivalenol, and HT-2 toxin, were analyzed simultaneously in rice, barley, and maize produced in 2011 by liquid chromatography coupled with triple quadrupole mass spectrometry (LC/MS/MS). Limits of detection (LOD) are 0.2 µg/kg for aflatoxin B 1 , and G 1 , 0.3 µg/kg for aflatoxins B 2 , and G 2 , 0.1 µg/kg for ochratoxin, fumonisins, zearalenone, and T-2 toxin and 3.0 µg/kg for deoxynivalenol and HT-2 toxin. Limits of quantification (LOQ) were 0.6 µg/kg for aflatoxins B 1 , and G 1 , 0.9 µg/kg for aflatoxins B 2 , and G 2 , 0.3 µg/kg for ochratoxin, fumonisins, zearalenone, and T-2 toxin and 10.0 µg/kg for deoxynivalenol and HT-2 toxin. Recoveries for 11 mycotoxins ranged from 70.45 to 111.11%. Fumonisins, deoxynivalenol, and zaeralenone were detected from 0.9 to 334.0 µg/kg in the polished rice, barley and raw corn cultivated in Korea. Other mycotoxins were not detected. Deoxynivalenol contamination was mainly found in barley (24 out of 43 samples) and the average value in positive samples was 113.30 µg/kg.