Abstract: (In this paper the authors continue to discuss some of the fundamental problems in the genetic improvement of Chinese Fir, which are as follows.)5 . The forms of the genetic mating design and the appropriate evaluation on each form and its applicationAfter comparing their virtues and defects of the designs, the authors consider that some of the designs, such as open-pollination progeny testing, blocked disconnected incomplete diallels and blocked nests polycross designs, etc., are suitable for commercial utilization. The complete diallel mating designs (Griffing’s Method 1 or 3 ) and the blocked complete diallels mating designs are recommendable in the field of theory research.6 . The intraspecies heterosis of Chinese FirIn this section, the phenomena of the intraspecies heterosis of Chinese Fir and its mechanism in quantitative genetics are discussed. The effects of combining ability of parents, especially the reciprocal effects are emphasized. The potential value of the self-breeding in the heterosis utilization is also expounded.7 . The early selection and predication in the improvement of Chinese Fir The subject discussed in this section deals with the reliability of early selection,the age for selection, and the annual genetic gains of early selection and predication.8 . The interaction of genetype and environment (GEI)The effects of GEI occur obviously in the progeny testing of Chinese Fir. The authors hold that the fine variety (or family) of Chinese Fir ought to be planted in places which suit its requirement of growth, and only under an intensive system of silviculture, can the potential of improved varieties to increase production be developed fully.