The invention discloses a manufacturing method of blood pressure lowering red rice, which comprises the following steps: preparing conversion mother solution with bracken as a raw material through low-temperature beating, converting glutamic acid or sodium glutamate into conversion solution containing gamma-aminobutyric acid through the conversion mother solution, adding nutritive substances intothe conversion solution, adjusting water content, bottling, sterilizing and inoculating monascus, fermenting culture medium with the inoculated monascus for 10-40 days at the temperature of 24-35 DEGC, drying products produced in fermentation, crushing the products and obtaining the blood pressure lowering red rice. The invention can solve the problem of taste caused by incomplete conversion of the glutamic acid or the sodium glutamate, the content of the gamma-aminobutyric acid in the blood pressure lowering red rice is high, and the blood pressure lowering red rice simultaneously contains Monacolin, K, monascus pigment, bracken flavone, ergosterol and other kinds of substances, and has the higher functions of lowering the blood pressure and improving the sleep.