Ortho-substituted styrenes, such as 2-(N,N-dimethylaminomethyl)styrene (1), 2-( 1-pyrrolidinylmethyl)styrene (2), and 2-[(S)-2-(1-pyrrolidinylmethyl)-1-pyrrolidinylmethyl] styrene (3), were synthesized, and the effects of the ortho-substituents on the polymerizability and stereoregularity of the obtained polymers using the anionic method were examined. The bulkiness and coordination of the ortho-substituted amino groups to the counter cation significantly affected the polymerizability and stereochemistry of the obtained polymers. The anionic and radical polymerizations of 2 with a less hindered ortho-substituent afforded polymers in good yields, whereas those of 1 and 3 resulted in lower yields. The anionic polymerization of 3 bearing an optically active diamine derivative at the ortho-position with n-butyllithium in toluene at 0 degreesC gave a polymer with a high stereoregularity and stable regular conformation based on the stereoregular backbone structure.