The function of proteins is engendered through their dynamic structural changes and dynamic interactions with other molecules. Although their direct real-space and real-time visualization is a straightforward approach to understanding the dynamic molecular processes, the lack of techniques has precluded it. Atomic force microscopy (AFM) is a versatile technique to image proteins in liquids at sub-molecular resolution, but its poor temporal resolution has meant an availability of only static or slow time-lapse images of proteins. Recently, this situation is, however, quickly changing. Over the past 15 years, studies toward increasing the scan speed of AFM and making high-speed imaging compatible with low-invasive imaging have been carried out at my lab. As a result, high-speed imaging, which is 1000 times faster than before, is achieved. This report presents exemplification of dynamic imaging of functioning biological samples.