Abstract: A 2-D(two-dimensional electrophoresis)protocol suitable for protein analysis in dendrobium leaf was set up．The protein extraction and protein excretion．as well as some key technologies of 2-D electrophoresis were studied．The results
showed that stable and clear 2D maps with about 613 protein spots could be obtained through the methods of extraction with trichloroacetic acid，isoelectric focusing under high-voltage and two-step equilibrium．

Key words: two-dimensional electrophoresis, proteome, Dendrobium orchids