AimsTo improve the -1,3-1,4-glucanase production by Rhizomucor miehei under solid-state fermentation (SSF) for industrial application. Methods and ResultsThe fermentation conditions for -1,3-1,4-glucanase production by R.miehei CAU432 under SSF were optimized using a one-factor-at-a-time' method. Under the optimized fermentation conditions, viz. oatmeal (045-09mm) as sole carbon source, 5% (w/w) peptone as sole nitrogen source, initial moisture of 80% (w/w), initial culture pH of 50, incubation temperature of 50 degrees C and incubation time of 6days, the highest -1,3-1,4-glucanase activity of 20025Ug(-1) dry substrate was achieved, which represents the highest yield for -1,3-1,4-glucanase production ever reported. The crude enzyme was extracted and purified to homogeneity with a purification fold of 46 and a recovery yield of 90%. The addition of the purified -1,3-1,4-glucanase in mash obviously reduced its filtration time (246%) and viscosity (261%). ConclusionsThe optimal fermentation conditions for maximal -1,3-1,4-glucanase production under SSF was obtained, and the enzyme was suitable for application in the malting process. Significance and Impact of the StudyThe high production yield and excellent capability of the enzyme may enable it great potential in industries, especially in brewing industry.