In this study, we proposed a formal definition and method for analyzing the customer journey, which has recently been used to analyze consumer behavior. Specifically, we defined the customer journey as a type of series data. We measured the distance between series using the new distances based on the Levenshtein distance and proposed clustering, nonparametric regression methods based on this distance. The results of the validation on actual data showed that the proposed method is valuable for pattern detection and forecasting. These findings can be used to analyze consumption behavior in the future.