Two-dimensional electrophoresis was used to analyze differential proteins between the perfect and imperfect flowers in Japanese apricot(Prunus mume Sieb.et Zucc).About 400 proteins were detected after analysis with software(PDQuest).One specific protein,one up-regulated proteins and twenty-one down-regulated proteins were found in the perfect flowers,two specific protein were found in the imperfect flowers,which might be related to the development of pistil.Three specific protein and five differential proteins were identified by mass spectrometry.And identified proteins were presented through the protein database,No.A7(28.2kD,pI 4.53)was related to the phytochrome B.