Nowadays, cable modem is an innovation for most people. The purpose of this research is to apply five factors that are "relative advantage", "compatibility", "complexity", "triability" and "observability" to adopting innovation in "innovation diffusion" theory. The aim is to discuss how they influence potential adopters ’ final decision. Focus group and survey was used in methodology. Demographic variables, media-use and adopting factors are three dimensions to probe potential adopters ’ decision. The first finding is that there ’s no significant difference between demographic variables and adopters ’ decision, and there ’s only "the online tool" has the significant difference with adopters ’ decision. Besides, people willing and unwilling to adopt cable modem have significant difference in "compatibility", "triability" and "observability". The secondary finding is: the motivations of adopting cable modem are fast-speed and reasonable price, and the reason of non-adopting is people don ’t know much about cable modem and in little demand of it.