ClpB, an ATP-fueled protein molecular machine, disentangles and reactivates aggregated proteins. By using high-speed atomic force microscopy, conformational dynamics of ClpB was visualized for the first time. ClpB forms open- and closed-ring, and the closed-ring was further classified into three forms; round, spiral, and twisted-half-spiral. These structures transformed each other during ATPase-cycle to perform protein disaggregation. This research will help to treat protein aggregations, which are related to various diseases and cause problems in industry.