This paper presents the projected structure of the T‐layer of Bacillus brevis, obtained from electron microscopic studies of the unstained protein layer in the frozen‐hydrated state. Computer image processing is used to correct for the effects of the contrast transfer function, and to increase the signal‐to‐noise ratio by lattice averaging. The results obtained show a good agreement with those previously obtained using negatively stained specimens. It is shown that the contrast of T‐layer embedded in ice can be approximated to pure phase contrast.