The present invention provides a method for evaluating (predicting, etc.) an individual difference (the tendency of every individual) in terms of drug sensitivity and disease vulnerability, comprising using a gene polymorphism of a cyclic AMP responsive element binding protein gene or the like. The method for evaluating drug sensitivity and the method for evaluating disease vulnerability according to the present invention comprise associating a gene polymorphism of a cyclic AMP responsive element binding protein gene or a haplotype constituted by the gene polymorphism with the drug sensitivity and disease vulnerability of an individual.