A series of blend membranes based on sulfonated poly(ether ether ketone) and poly(4-styrenesulfonic acid) are prepared by solution casting method. The conjunction of the two polymers is evaluated by Fourier Transform Infrared Spectroscopy technique. The thermal stability is determined by Thermogravimetry Analysis. The blend membranes are investigated in terms of swelling behavior, methanol permeability and proton conduction. The Uptake in water and methanol solution distinctly increases with the increasing of the poly(4-styrenesulfonic acid) content. Methanol permeability slightly increases with the increase of the poly(4-styrenesulfonic acid) content and then reaches to a stable value. The proton conductivity is improved with increasing of the poly(4-styrenesulfonic acid) content. The calculated activation energy for proton transportation is similar to 6 kJ mol(-1), which shows that proton can easily conduct through the polymer network. The blend membranes containing 30 wt.% of poly(4-styrenesulfonic acid) are applied in the practical direct methanol fuel cells and their polarization curves with 2.0 mol L-1 methanol solution are measured. The max power density is as high as 28.82 mW cm(-2) at 100 mA cm(-2) (80 degrees C). All the results indicate that these membranes based on sulfonated poly(ether ether ketone) and poly(4-styrenesulfonic acid) show good prospect in direct methanol fuel cells. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.