Abstract: Two hundred and one Pyrus pyrifolia（Burm.）germplasms[involved Nakai（P. serotina Rehd.）P. bretschneideri Rehd.，P. ussuriensis Maxim. and Pyrus communis L.] were further analyzed by the method of SSR，and 36 pear resources of them were determined as the core collection of cold region in this study：Included 26 kinds of P. ussuriensis Maxim.，which accounted for 16.9% of the original germplasms of P. ussuriensis Maxim.，5 of P. bretschneideri Rehd.，which accounted for 50% of the original germplasms of P. bretschneideri Rehd.，4 kinds of P. pyrifolia（Burm.） Nakai（P. serotina Rehd.），which accounted for 21.1% of the original germplasms of P. pyrifolia（Burm.）Nakai（P. serotina Rehd.） and 1 kind of P. communis L.，which accounted for 11.1% of the original germplasms of P. communis L.

Key words: pear, resource, cold region, SSR, core germplasm