Abstract: The endogenous inhibitors in Masson pine( Pinus massoniana Lamb.)cuttings(MI n )from the ortets of five different provenances and from ten ortets in Jiangxi provenance,were purified and separated by the methods of extraction and high pressure liquid chromatography(HPLC).The properties of the MI n were preliminarily proofed by means of chemical detection and ultraviolet absorption spectra followed by biological assay with seed germination percentage of Pinus yunnanensis Franch.Seven components were found in each cutting,four were flavones and three were phenols.The rooting rate of each kind of cuttings negatively correlated with their MI n contents.The contents of MI n in different cuttings were compared by HPLC auto integrator.The relative contents of MI 2,MI 3,MI 4 and MI 5 in cuttings from the five provenances were notably different.MI 1,MI 6 and MI 7 were very notably different.The total relative content of MI n in Jiangxi provenance was the highest,and the lowest in Guangdong provenance.The relative content of MI 2 was notably correlated with longitude,but MI 4 and MI 5 were negatively correlated with latitude.The relative contents of MI 4,MI 6 and MI 7 in ten ortets from Jiangxi provenance were notably different,and MI 1,MI 2,MI 3 and MI 5 were very notably different.MI n in No.3 ortet was the highest and No.9 the lowest.These all held an identical result with the cutting rooting test.The exist of MI n in cuttings was one of the reasons why Masson pine cuttings were difficult to root and why rootability of each kind of cutting was variant.Stopping the express of the MI n genes would be the successful way for increassing the cutting rooting rate.