Abstract: On a field trial on mycorrhizal tissue culture seedlings of Eucalyptus grandis × Europhylla with Pisolithus tinctorius (P.t.), it was found that the P.t had sustained more than 10 years, but inoculated Hebeloma westraliense and Laccaria laccata had sustained only from 2～6 years, then the two fungus species were substituted by other mycorrhizal species fungi. In nature, no-innoculated trees of E. golbulus were Scleroderma and Lacaaria as dominant fungus species from 2～4 years after planting, then they were respectively substituted by Cantharellus spp. and Boletus spp.. Tricholoma matsutake could persist more than 10 years in natural forests,which had high persistence ability. On inoculated seedlings of Pinus yunnanensis, mycelia of Tricholoma matsutake grew well from 1～6 years after planting. The succession and persistence of mycorrhizal fungus had been concerned with the fungus characteristics. If the fungus was suitable to local environment condition, the fungus growth and development had persisted for long time, otherwise the fungus could be substituted by other fungi. We suggested that the mycorrhizal fungus application should follow the principle-suitable fungus for suitable land and suitable fungus for suitable trees. Only in this way,the effectiveness of mycorrhizal fungus would persist and benefit.