Abstract:During the year 1974—1978, a study on the growth condition and the regulation of seed bearing of scotch pine have been carried in Honghaergi Hulunbaier district.It can be accelerated the growth of breast-height diameter in full light whereas the height growth is somewhat inhibited.Although scotch pine is a indigenous species in frigid temperature zones, the annual average temperature is less than -5℃ or less than 15℃ in June, that these factors are not favourable for the height growth.The precipitation in June is the major factor to affect the height growth of scotch pine, but it does‘nt affect too much.When the rain and heat are synchronism, the growth in height is the fastest.Scotch pine begins its seed-bearing at 10 year old, and heavy crops at 30. The seed production is increased with the age, and the quality will be decreased over 80 years old. It is concerned with its breast diameter, height growth and the width of crown.When the stand canopy density is 0.5, the seed production in the unit area is the heightest.