A lithography technique for fabricating subwavelength surface relief grating features based on evanescent waves interference is investigated by both analytical and numerical approaches. The analytical expressions for the intensity profiles of evanescent waves interference generated by both s- and p-polarized incident plane waves are deduced. The corresponding resist topologies are computed using a numerical scheme based on a modified cellular automata model, as proposed. The influences of polarization and exposure duration on patterning by evanescent waves interference lithography are investigated. The results suggest that this technique is capable to achieve nanoscale line features with linewidths as small as 15 nm, a pitch size of 105 nm, and an aspect ratio as high as 10.7 by appropriate choice of exposure duration and state of polarization for the incident beams.