Abstract: The symbolization time series cluster is one of hot spots in the clustering research.The key to question is similarity in signifying of time series.This paper puts forward the ELCS similarity measure based on the defects existed in the traditional Euclidean distance metric, and on foundation of the LCS measure.It can overcome the shortcomings of the LCS measure which rely on the selection of linear function.The experiment on two types of data sets shows that compared with other common measure, this measure has a better clustering effect.