Abstract The red yeast rice was the product of fermented rice by Monascus purpureus. Metabolic processes during fermentation produce contents of secondary metabolites, such as pigment, monacolin K and citrinin. Citrinin has antimicrobial activities but its have nephrotoxic and hepatotoxic mycotoxin effects. The isolation and determination of citrinin by solid fermentation Monascus purpureus from various isolates have been done using rice as a substrate. The red yeast rice product was extracted using methanol. Citrinin levels of several red yeast rice products were measured using High-Performance Liquid Chromatography at 330nm and 500nm with acetonitrile: phosphoric acid 0.2% (1:1), using a C18 column with a flow rate of 1ml/min. The curve of Citrinin standard linearity was created with some concentrations and produced the linear equation which was y = 71048x + 47811 with a value of r = 0.9998. The citrinin levels from several different red yeast rice products were red yeast rice of A 369.97 ng/ml, B 0.85 ng/ml, C 70.48 ng/ml, D 3.59 ng/ml and of E 790.17 ng/ml. The research showed that the different isolates of Monascus purpureus could influence the production of citrinin levels whereas the isolates of Monascus purpureus E has the highest citrinin levels. This citrinin level was considered safe to use because have not effected for nephrotoxic and hepatotoxic.