Provided is a pharmaceutical composition for preventing or treating neuronal diseases comprising, as an active ingredient, an exon 2-deleted AIMP2 variant (AIMP2-DX2) gene or a vector comprising the gene, and a method for treating neuronal diseases in animals other than humans, comprising administering the same to a subject in need of treatment. The pharmaceutical composition comprising, as an active ingredient, a AIMP2-DX2 gene or a vector comprising the gene has the effects of apoptosis inhibition, dyskinesia amelioration and oxidative stress inhibition and thus can be widely used for preventing and treating neuronal diseases such as Parkinson's disease and amyotrophic lateral sclerosis.