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( m CPP) to induce anxiety. RESULTS m CPP 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. m CPP 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 m CPP-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.