Abstract: Protein markers were used with optimal electrophoresis conditions in analysis of proteins of phase change in apple.Optimal conditions for non-gel sieving capillary electrophoresis (NGSCE) were 0.15 mol.L-1 TB, 0.1% SDS, 7.5% Dex tran, 7.5% glycerol, 23.5 kV separation voltage and 1.5 psi×90 s injection volume. This condition for NGSCE was used to separate the phloem proteins in apple hybrid seedlings. A 5.0-kDa protein appeared above the 50th node, and the content of a 24.5-kDa protein increased sharply during phase change. The result was valuable for study of apple phase change.