Objective:Different concentration growth regulating substances of 6-BA,NAA,2,4-D and PP 333 on pollen germination and pollen tube growth were studied with pyrus pyrifoliaWhangkeumbae.Method:Pollen cultivating liquid medium were confected,with different mass concentrations of 6-BA,NAA,2,4-D and PP 333.To research the effects of different concentrations plant growth regulating substances on pollen germination and pollen tube growth.Result:Results showed that the low concentration of 6-BA and 2,4-D stimulated the pollen germination and pollen tube growth,but when the concentration up to certain value,pollen growth and pollen tube growth were inhibited.NAA and PP333 had inhibition on pollen germination and pollen tube growth.Conclusion:10 mg /L 6-BA and 5 mg /L 2,4-D stimulated the pollen germination and pollen tube growth.