The capabilities of time-of-flight secondary ion mass spectrometry (TOF-SIMS) with regards to limits in lateral resolution for biological samples are examined using supported lipid bilayers and individual lipid vesicles, both being among the most commonly used cell membrane mimics. Using supported 1-palmitoyl-2-oleoyl-sn-glycero3-phosphocholine (POPC) bilayers confined to a SiO2 substrate by a chemically modified gold surface, the edge of the lipid bilayer was analyzed by imaging TOFSIMS to assess the lateral resolution. The results using 80 keV Bi32+ primary ions show that, under optimized conditions, mass spectrometry imaging of specific unlabeled lipid fragments is possible with sub-100 nm lateral resolution. Comparison of the secondary ion yields for the phosphocholine ion (m/z 184) from a POPC bilayer using C60+ or Bi3+ primary ions showed similar results, indicating an advantage of Bi3+ primary ions for high-resolution imaging of lipid membranes, due to their better demonstrated focusing capability. Moreover, using 300 nm vesicles of different lipid composition, the capability to detect and chemically identify individual submicrometer lipid vesicles at separations down to ~ 1 μm is demonstrated.