The purpose of this study was to analyze treatment effect for skin aging according to changes of fluence and pulse duration of 1064nm Nd:YAG laser. For this purpose, we designed skin model composed of epidermis, dermis, and fat, and each layer had similar thickness of facial skin. Environmental temperature was set to 26°C, and the initial temperature of each skin layer was designated as human body temperature (36.5°C). The fluence of the treatment laser was divided into 8, 9 and 10J/cm 2 , and the pulse duration was classified to 0.35, 0.50, 0.70 and 1.00ms, respectively. Based on experimental results, we found that the skin temperature increased along with penetration depth as increase in fluence. In addition, the treatment condition with fluence of 8J/cm 2 and pulse duration of 0.7ms, as well as fluence of 9J/cm 2 and pulse duration of 0.5ms, transmitted the heat into the dermis most effectively without any skin damage.