Territrem B is a tremogenic mycotoxin produced by Aspergillus terreus. Animal studies have demonstrated that territrem B caused whole body tremor, salivation, convulsion and death. Territrem B is also a potent irreversible inhibitor of acetylcholinesterase (AchE, E. C. 3.1.1.7). The aim of the present study is to assess the ability of strains of Aspergillus terreuss to produce territrem B in the rice media, which were obtained from Food Industry Research and Development Institute in Taiwan. In the 17 strains of A. terreus, only No. 32111 and 32664 strains produced territrem B-like blue fluorescence compound by TLC and HPLC analyses. Later on, this compound was identified as territrem B by mass spectroscopy. The amount of territrem B was determined by reverse phase HPLC on a C18 column with UV detection at 335 nm. The linear regression coefficient of the standard curve (Y=1428.5X+306.0) for territrem B at concentration ranging from 0 to 250 ng/L is 0.9998. In rice media, the recovery rates for territrem B at 50, 100 and 200 ng/L ranged from 91.5% to 95.2% with a coefficient of variation less than 2.1%. The relative standard of territrem B ranged between 1.6-2.8% (intra-day) and 0.6-2.3% (interday). In rice culture of A. terreus 32111 and 32664 strains, the contents of territrem B were 0.20 and 0.31 mg/100 g rice, respectively. From the above results, it can be concluded that this HPLC method for determination of territrem B in rice media is suitable and only domestic strains can produce territrem B.