Abstract: Investigations have been made on the seasonal variation in height growth, diameter growth and net photosynthetic rates (NPR) of the needles of young Pinus massoniana Lamb. (2 to 6 years old) in Guanzhuang Forest Station, Fujian province during the years of 1983 and 1984.There exists a positive relationship between spring-shoot length and apical bud size. The growth rate of spring shoots is closely correlated to air temperatures. The air temperatures favorable to the growth of spring shoots range from 8°Cto 30°C. (the average temperature of ten days) with the highest growth rate at 20°C.The measurements made in 1983 show that the seasonal changes of diameter growth accord with the seasonal fluctuations of rainfall and NPR of needles. The average daily NPR of one-year-old needles reaches a peak value by the end of May, declines obviously from July to September due to drought, and then gets to a second peak value in October.