With monascus M2 as the research object,on the basis of single factor experiment,ranges of the four factors including inorganic salt water adding amount,incubation time,incubation temperature and medium initial pH value were determined. In addition,orthogonal experiment was designed with raw-starch-digesting amylase activity as an index to optimize the culture condition,and some properties of amylase under the optimal conditions were studied.Results showed that the,,enzyme activity reached 445. 37 u / g in 14mL inorganic salt water incubated at 32℃ and pH 5. 0 for 6d. Optimum reaction temperature for the enzyme was 40℃. The optimum pH was 5. 0,and the enzyme was relatively stable at pH 5. 0 ~ 7. 0. The residual enzyme activity was only 23. 9% after incubation at 60℃ for 2h because of its low thermal stability. Zn2 +,Mn2 +,Cu2 +could promote the activity of the enzyme,Ba2 +and Fe3 +could inhibit its activity,and Na+,K+,Mg2 +have no effect on it.