Abstract: Possessing pores is one of the inherent characteristic of P/M products.It's necessary that materials possess certain porosity for some applications, for example oil-bearings, filters.but it might be detrimental for other application,Impregnation process is a method for sealing the pores inside the P/M products and has been developped a new field for the applicating of P/M products. After having been im pregnated P/M products can be plated, painted satisfyingly and machined easily. The new development of impregnation technique and sealing agent were presented in this paper. Meanwhile the impregnation process and new device in vacuum condition and the research results of impregnation sealing were also described.