The methods to preventing the explant and its calli from browning in the processes of vitro propagation of Pinus thunhergii were stu died.The result showed that mature embryo of P.thunhergii is a better explan t than new shoot for its lower browning death rate.Culturing at dark is a necess ary condition for avoiding browning.Adding Vc and active carbon cannot overcome the browning of the calli.Selecting suitable medium (1/2MS) and using proper ho rmones at certain concentrations could prevent browning and increase growth effe ctively.