Abstract: The changes in potentials and pH values of the solution gave rise to variations of colour and electronic absorption spectra of poly-o-methylaniline film. However, its colour did not change with potential and polymer lost its electrochemical activities in the solution of pH 4.13. The g-value was 2.0027 and was not affected by the kinds of doped anions and hydrolysis. The ΔH_(p-p) was 1.6G. It did not depend onthe kinds of doped anions, but was affected by hydrolysis. The magnetic suscepti-billity of poly-o-methylaniline was not measurable at 0.8 to 4 kG magnetic field.