Carbon-13 spin-lattice relaxation time (T1) and nuclear Overhauser factor (NOE) series of 1

2-polybutadiene samples with different microstructures in four different solvents were measured at 50.3 MHz. The data were fit by using Schaefer's asymmetrical logx2 distribution. The relationship between solvent effect on 13C NMR relaxation and the structure of 1

2-polybudiene was studied. It was found that with the increase of the difference of solubility parameters between polymer and solvent (A S)

the extent of cooperative segmental motion of the polymer in solution tends to be easier and spin-lattice relaxation rate (1/T1) becomes greater. When 1

2-unit content decreases and main chain becomes more flexible

the effect of solventon 13C-NMR relaxation becomes more considerable. NMR relaxation parameters are more sensitive to the variation of structure in good than in poor solvents.