Objective: In order to improve the comprehensive utilization value of corn steep liquor, fermentable corn steep liquor was used to partially replace bran for cultivation of Pleurotus eryngii. Methods: 6 percent of the nitrogen source in the traditional matrix was replaced by fermentable corn steep liquor in the cultivation of P. eryngii, and the differences in non-volatile flavor composition and nutritional value were analyzed by measuring the content and composition of free amino acids, organic acids, soluble glycol, 5'-nucleotides. Results: The results showed that the chemical scores of P. eryngii amino acids were 50.31 and 48.93, the BV values were 157.99 and 144.61, and the NI values were 30.8 and 28.0 respectively; EAARR values were 0.854 and 1.025, and the nutritional value of the experimental group was higher than that of the control group under the multi-evaluation system, in which the content of aromatic amino acids was 24.187 g/100 g; the soluble glycol content was 32.14 g/100 g, and the organic acid content was 4 277.258 mg/kg, 5'-nucleotide content was 280.05 mg/100 g were higher than the control group. Comprehensive analysis of the equivalent umami concentration EUC experimental group （595.14 g MSG/100 g） umami higher effect than the control group（565.65 g MSG/100 g）, and the umami taste was obvious and strong. Conclusion: The nutrient value and the content of non-volatile flavoring substances in the fruiting body of P. eryngii could be significantly increased by using corn slurry fermentation liquid to partially replace the nitrogen source in the traditional culture medium.