Abstract: Based on the electro-chemical modification comparison test of mudstone from the coal measure strata under aqueous solution in purified water and 1 mol / L NaCl water solution and by combining the results of liquid nitrogen ad- sorption,uniaxial compression test and scanning electron microscopy energy dispersive spectrum ( SEM-EDS), the change rules of pore and strength of mudstone for different zone under electro-chemical were studied. Following results have been gotten:The electro-chemical corrosion of electrode and wire occurred mainly in anodic zone,and the corro- sion degree of anodic electrode in 1 mol / L NaCl water solution is significantly heavier than in purified water. After e- lectro-chemical modification,the accumulated surface area and pore volume of samples from anodic and cathodic zone decrease with different degrees when compared with the samples in the state of nature,and the declined level of the ac- cumulated surface area of samples from cathodic zone is heavier than that from anodic zone,while the decreased rating of the accumulated pore volume of samples from cathodic zone is less than from anodic zone. The accumulated surface area and pore volume of samples from anodic and cathodic zone with 1 mol / L NaCl water solution were larger than that with purified water. The uniaxial compressive strength (UCS),elastic modulus (E) and deformation modulus (Ed) of the electrochemical modified samples is significantly higher than that of the unmodified samples,and the strength of samples in 1 mol / L NaCl water solution is higher than that in purified water.