Abstract: Tissue culture technique, paper sandwich mycorrhization technique and root truncating cultivation with mycorrhiza in nursery were used to make Pisolithus tinctorius RG310 and RG49 to form endo ectotrophic mycrrhiza on Pinus massoniana, P.taeda and P.elliottii. There are differences in the process and type of mycorrhiza formation among different mycorrhization techniques above mentioned. By using the tissue culture mycorrhization technique, the mantle formed in the third or fourth day after the fungi got in touch with the roots, and began to form Hartig net on the eighth day,the hyphae entered the cortical cells on the 18th day, the inoculation intensity increased with the time extension, the Hartig net formed from the single line hyphae to multi lines hyphae. The paper sandwich myorrhization technique was used to promote the colonization of mycorrhizal fungi,shorten the inoculation process and accelerate the mycorrhiza formation. Cutting the surface wound is taken as the main way, which enlarged the MIZ inside outside the root and transformed the inoculation procedure.The colonization and inoculation occurred at the same time, the mantle, Hartig net and hyphae inside cells formed nearly at the same time. A new mycorrhiza type-ecto endomycorrhizae formed only within 25 hours and the hyphae entered not only the cortical cells but also the pith. THe root truncating cultivation with mycorrhiza in nursery could also form ento endomycorrhiza, but the hyphae could not enter the root tissue inside enodermis. Based on reasearch, the hypothesis "mycorrhiza type" is put forward, i.e. the mycorrhiza type formed by trees varies not only with the species of fungi and tree,but also with the mycorrhization techniques, ecological conditions etc.