Abstract: Chinese ash wood was systematically studied on the anatomical properties and their variation patterns by constituting sample plot, selecting standard sample trees, stemanalysis, timber segregation observation, using electronic microscopic and micrograph analysis system of computer, and approaches of quantitative anatomy were used from a microscopic aspect. The results showed that Chinese ash wood was ringporous wood and had many longitudinal parenchyma, the early wood vessel was round or oval, wood ray was homeotype ray .The fiber length, width, cavity, doublethickness, ratio of wood cell wall thickness to lumen of the radial ground up were 500—1 428 μm，10—24 μm, 7—20 μm, 1.4—4.6 μm, 0.25—0.58. Between growth rings and tree height, the variations of the fiber length, fiber width, fiber doublethickness, ratio of fiber length to width, ratio of wood cell wall thickness were significant.