Structure of electromagnetic pilot valve used in electro-hydraulic support for hydraulic support of fully mechanized coal mining face was researched. At first, common fault causes of electromagnetic pilot operated valve was analyzed, and increasing valve core opening of electromagnetic pilot valve to improve its anti clogging ability was proposed. Then in order to ensure its excellent response ability, solenoid pilot valve core opening and reset valve parameter of electromagnetic pilot valve were optimally designed. Finally, Simulink simulation software was used to make simulation analysis for dynamic performance of electromagnetic pilot valve after optimization. The results showed that after optimization, electromagnetic precursor valve had advantages of short response time and good dynamic performance which could meet operating requirements.