Nowadays, online petition become a tool that can be used to persuade public to care and give a support by signing the petition online at change.org. There are not least number of petitions that were declared successful because they get a lot of signatures, and some or all of the claims presented in the petition are met. This study aims to find out what are the motives of someone signing a petition and the route of decision that they passed when they sign the petition based on the theory Elaboration Likelihood Model. This study used a qualitative approach with case study method and the data collection was done through in-depth interviews with informants and direct observation of the site change.org. These results indicate that there are six motives that drives a person to sign the petition on change.org. The motive when associated with the persuasion process based on the Elaboration Likelihood Model of persuasion get the two routes that can be passed when someone wants to sign a petition, there are Central Route and Middle Route. The findings on middle route is a finding from the study, because it shows that a reader may be tempted to sign the petition for the same motive but with different routes.