The extracellular and periplasmic surface topography of the E. coli outer membrane protein OmpF reconstituted into 2D crystals in the presence of phospholipids were investigated with a scanning force microscope in buffer solution. Topographs exhibiting 2 nm lateral resolution are in good agreement with data from electron microscopy and x-ray crystallography, and indicate the exciting possibility to monitor structural changes of "live systems" at molecular resolution by scanning force microscopy.