Abstract:The tree introduction test results show that Taiwania flousiana seedling grows slowly and seedling growth curve appears to be "M" shape with double growth peaks, owing to the fact that it grows fast in spring and autum, but tends to stop in hot summer. During the initial stage of planttation, the young tree seedling grows slowly, but after 3 years it grows faster and faster and from the 5th to 10th year, it grows very fast. Annual growth of seedling is near or above its provenance growth. Seasonal growth reqularity of T. flousiana seedling is that it grows fast during the late spring and early summer (May and June), its growth peak appears in June, and then, the growth speed slows down in hot summer because of the high temperature, therefore the growth curve shows only one peak as a reversal “V” shape. Day-night growth of young T. flousiana seedling shows night> days the daily growth appears in that order: rainy day> cloudy day> shiny day. The following factors are the important ones which influence the young tree growth: air temperature, relative humidity and shining hours on the introduction locality. The relationship between young tree growth and seedling age could be expressed by the model of y =a+bt; the model y =a +blnt can be used to express the relationship between seedling growth and the observation month, and the average annual growth, annual increment and monthly net increment could be described by the model y=a+bt ct2.