For getting an ideal method of extracting poplar genomic DNA, the CTAB method of extracting plant genomic DNA of Clark’s was improved according to the experiences of ourselves. A series of substance for rejecting protein, phenolic compound and MgCl2 for settling DNA were added into the improved method. The experiment compared the improved method with other three traditional methods，the quality of the DNA was examined with UV analysis and agarose gel e1ectrophoresis,then the results were showed to obtain high quality DNA with the improved method. It is optimum and suitable for RAPD and other molecular biology researches. In addition, five poplar genomic DNA were extracted with the improved method, amplified successfully with primer S174 and identified in the experiment.
