Disclosed are a method for data de-duplication and an apparatus for the same. The method may comprise obtaining access property of data based on input request or output request for the data, determining de-duplication unit of the data based on the access property, and performing de-duplication on the data based on the de-duplication unit. Thus, data de-duplication rate may be determined adaptively based on input/output characteristics of data. Also, data de-duplication may be performed based on the determined data de-duplication rate so as to provide low input/output latency.