A study was conducted to investigate the exfoliated structure of sulfonated poly(arylene suofone) (sPAS) clay nanocomposites. The clay nanocomposites show excellent mechanical strength and methanol permeability at high proton conductivity. The nanocomposite membrane with these properties can be used for direct methanol fuel cell (DMFCs) applications. The study prepared sPAS-clay nanocomposites without organic modifiers that can be used to reduce the electrochemical stability and mechanical strength of the composites. It was observed during the study that the dispersion state of clay layers can improve the mechanical strength and methanol permeability without making any harm ion conductivity. The study also found that the exfoliated clay nanocomposites has higher surface area for interacting with the sPAS.