Theoretical spindensity distributions and theoretical coupling constants of th-y mine ionic radicals and hydrogen abstruction radicals have been calculated at INDO level. The atomic coordinates of their conformations were obtained from a "mixed geometrical model". In the case of thymine anion radical and the hydrogen abstruction derived radical from the methyl grop of thymine, the theoretical coupling constats agree with the experimental data very well. In the case of the thymine cation radical and the hydrogen abstraction radical resulting form N1 of thymine, the calculated results agree with calculated values given by other authors and agree approximately with the experimental data.