Abstract: The dynamic variations of protein vacuoles in the egg cells of Pinus tabulaeformis Carr.were studied using the paraffin-cross section method.The specific proteins relating to the development of egg cells were analyzed with two-dimensional electrophoresis(IEF/SDS-PAGE) and ImageMaster^TM2D Platinum.The results indicated that archegonia,which was filled with vacuoles,emerged at the beginning of May.With the disappearing of vacuoles,many protein vacuoles appeared from the bottom and periphery of egg cells.The number of protein vacuoles reached high peak just before fertilization,and the number and volume of protein vacuoles decreased when the egg cells were fertilized.After sperm-oocyte fusion,protein vacuoles disappeared immediately.At the same time,saccharides and proteins changed regularly in the embryos.Furthermore,there were four new proteins appeared,ten proteins disappeared and the other ten proteins decreased during the development from archegonia formation to fertilized egg cells.