The process of implementing risk management systems for the organizations in financial service industry can be viewed as a diffusion of innovation since the introduction of the risk management systems changes the decision making process on risks faced by the organizations. The purpose of the reported research is to examine the factors that affect the successful implementation of ALM(asset & liability management) systems, the risk management systems managing interest rate risk. Specifically, this paper presents an investigation of three factors from the diffusion of innovation studies; internal factors, external factors, and time. A field survey was conducted for Korean banks that have implemented ALM systems. The results suggest that the perceived uncertainty of market, system supports, and management supports be most significantly related to the successful implementation of the risk management systems. The findings of the current study also suggest a certain amount of time should be passed to diffuse the risk management systems in organizations.