X-ray crystallography of kinesin enzymes in the unstable intermediate states is challenging because an uniform shape of protein is required for its crystallization. Using nucleotide analogs is one of the frequently-used techniques to solve this problem. We previously used ATP and ADP-phosphate analogs to solve the crystal structures of kinesin ATPase before and just at the point of ATP hydrolysis (1-3). However, since there are no analogs suitable for the Mg- and ADP-releasing processes, crystallization of these processes has been perceived to have many challenges and difficulties. The protocol outlined below describes how we have succeeded in crystallizing kinesin in the Mg-releasing intermediate states. Albeit this protocol will not be a panacea for all enzymes, we hope this procedure might be helpful in crystallizing some other enzymes in this transitional state.