本論文內容分成兩部分．前半部分探討臉書從一般社群網站企業成為平台企業的過程並以MySpace作為比較對象，得到結果為臉書因本質上的不同才是其成為社群網站之王的原因，並非皆因其開放平台．後半部分探討臉書成為平台企業後，如何打造其生態圈。本研究歸納出臉書利用平台技術策略之更新、收購、應用軟體策略佈局來打造生態圈．;This thesis is divided into two parts. One part is about the process that how Facebook become a platform company. Also, I choose the most similar social network site , MySpace , as the comparison. The result of this part is that Facebook becomes king of SNS is because its essence and the strategy of opening platform. The other part of this thesis is talk about how Facebook build its own ecosystem after it becomes a platform company. I arranged this process under three main heads: the updated technique and strategies of platforms, acquisitions and strategies of applications.