The features of Instant Customerization were given by the comparison of traditional production mode with Instant Customerization one. After analysis of the traits of the market in Instant Customerization, the concept of enterprise' production capacity and its characteristics in Instant Customerization was presented. The characteristics of production capacity of Instant Customerization were also analyzed by discussing the concepts of production capacity among Mass Customization, supply chain system and Instant Customerization. According to the case of DELL mode, the mechanisms accumulated by the enterprises' production capacities in Instant Customerization were studied