Abstract: The conductivity and methanol diffusion resistance would decide the applied properties of the proton exchange membrane (PEM) that should be a key part of the direct methanol fuel cell (DMF). In this work, the conductivity and the methanol diffusion resistance of SPEEK-PEM were evaluated with the improved two-poles AC measurement device and the diffusion cell with the refractometer which were designed by us selves, respectively. The test results showed that the good data repeatability, enough sensitivity and distinguish ability for the different material membranes were obtained with these methods.