The behavior of fox adsorption and desorption of the NOx storage catalyst supported on Ba additive were studied by the TPA/TPD experiments and reactivity tests. Applying the transient responses and NOx TPA/TPD test by CLD were effective methods to analyze the characteristics of the NOx storage catalyst. NOx variation of the NOx storage catalyst in the lean air/fuel conditions according to temperature was dominated by NOx adsorption and desorption rather than catalytic reduction. The presence of reductants in the lean mixture promoted the NOx desorption at the $500^{circ}C$ higher temperature. The temperatures for maximum NOx conversion with CH4 and $C_3H_6$ as a rich spike reductant appear around $500^{circ}C;and; 400^{circ}C$ respectively.