Abstract: AIM　To develop a new economic and simple anxiety model that mimics clinical conditions for screening and studying anxiolytic agents. METHODS　The behavior activity of ddy and ICR mice in light-dark box was observed after sc m-chlorophenylpiperazine(mCPP) to induce anxiety. RESULTS　mCPP was shown to significantly decrease the activity of ddy mice in light box after sc 1～4 mg.kg^-1, but the activity in dark box was not significantly changed. No significant difference was found in the light box between the 1 mg.kg^-1 and the 4 mg.kg^-1 group. mCPP showed little effect on the activity of ICR mice in the light box, but it was shown to significantly decrease the activity in the dark box between 2～10 mg.kg^-1. It is easy to show the anxiolytic effect of diazepam only in a small sample by using ddy mice in this model. CONCLUSION　It is easy to get effective result by using only a small sample in the light-dark box after mCPP-induced anxiety in ddy mice. It appears that this model is an economic and simple anxiety model that mimics clinical conditions for screening and studying anxiolytic agents.