Disclosed is a method for mashing up heterogeneous sensors, which includes collecting an activity log from at least one sensor, converting the collected activity log into a common markup format, extracting an activity of a user from the activity log, based on an activity model which defines relations among activities, and outputting the extracted activity of the user in a semantic unit. Thus, it is possible to integrally utilize information of heterogeneous sensors, provide meaningful and intuitive information to a user, and share information of various applications and devices.