An inter laboratory study was conducted to evaluate an application of the AOAC Official Method of Analysis for the determination of ochratoxin A (OTA) in barley to brown rice as a new matrix. Four artificially OTA contaminated brown rice test samples (blind duplicates at two levels), six OTA spiked brown rice test samples (blind duplicates at three levels) and two blank brown rice (blind duplicates) were sent to 12 collaborators. These samples were analyzed by a designated method. From the results, the RSD_r values ranged from 3.4 to 8.9 % at the OTA concentrations of 0.5 to 40 μg/kg and the RSD_R values ranged from 9.6 to 21.3 % at the same OTA concentrations, respectively. The HorRat ranged from 0.4 to 1. These results allowed us to conclude that the AOAC Official Method of Analysis for OTA in barley (49.6.04) showed acceptable for brown rice at the OTA levels ranging of 0.5 to 40 μg/kg. Recently, as LC-MS analysis for determination of OTA was reported, LC-MS analysis fixed the LC-MS conditions in our laboratory was examined the same extracts obtained from the test samples by 8 of 12 collaborators. From the results of this test, LC-MS analysis was confirmed acceptable at the OTA levels ranging of 10 to 40 μg/kg.