Abstract:Total DNA in leaf tissue of Fagus engleriana was extracted by four methods. Improved CTAB method was proved as the best one. The DNA sample obtained by this method was fit for RAPD experiment. RAPD reaction system(25 μL):40ng DNA template, 0.8 μmol·L-1 primer,Taq DNA polymerase 1.25 U, 2.0 mmol·L-1 Mg2+, 0.16 mmol·L-1 each dNTP. PCR amplification program was denaturation at 94℃ in advance for 3 min,then followed by 45 cycles,each cycle: denaturation at 94℃ for 30 s,anneal at 37℃ for 1 min and extention at 72℃ for 2 min.