Digital currency rose to its prominence in 2009, marked by the birth of Bitcoin. The following seven years saw the burgeoning of a 10 billion dollar worth Bitcoin global network, which leads to more discussions from central banks around how to keep up with the trend both systematically and technologically. Debates on the legitimacy of digital currency never end, with speculation around possibilities of its replacement of fiat money, an ensuing prospective governance mechanism and its function akin to that of central banks. If these bold assumptions failed, can this monetary innovation work as a compliment to central bank policies and currency system? This article will look into the above possibilities and assumptions on the basis of existing researches, technologies and regulations, in hope for an all-round thinking and further discussions without giving away any affirmative conclusion due to the complicity of monetary system and early development of digital currency.