Abstract: Liquid poly-butadiene telomers (Mn800-3000, vinyl content 10-60%) were prepared by using n-butyl lithium-potassium butoxide as catalyst, toluene as solvent, with the addition of different polar modifiers (TMEDA, 4G, 2G, HMPA). The effects of concentration and composition of initiator, concentration of polar modifiers, temperature etc. on the reaction were investigated. The optimal reaction conditions determined were: concentration of initiator k'=1-2mol×10^-3/75g Bd, relative composition of initiator k"=0.1-0.6, reaction temperature 40-70℃, relative composition of polar modifier k″′≤3.0 (TMEDA).