Disclosed in the present invention are a cannabinoid composition and an application thereof in the preparation of a drug for treating neurodegenerative diseases, for use in solving the existing problems of large side effects and poorer therapeutic efficacy after long-term use of a drug for treating neurodegenerative diseases. The cannabinoid composition comprises cannabidiol and cannabigerol which are in a mass ratio of 1:1-1:10 or 1:0.3-1:0.5 or 1:0.5-1:0.7 or 1:0.7-1:1. According to the present invention, by using an experimental method for inducing the differentiation of fibroblasts into dopamine nerve cells to observe the morphologies and number of cells after the inducing of cell differentiation and detect an expression level of DA-related factors, and to screen effects of common different cannabinoids and combinations thereof on the inducing of the differentiation of fibroblasts into dopaminergic neurons, it is found that a CBD+CBG combination has optimal effects on the improvement of the survival ability and dopamine secreting ability of the dopaminergic neurons, does not contain the addictive substance THC and thus greatly reduces the side effects of a drug, and can be used for preparing a drug for treating neurodegenerative diseases.