Digital currency can reduce the issuance and circulation costs of physical cash and improve the convenience and transparency of economic activities. Therefore, digital currency has received widespread attention from central banks in recent years. As an important financial infrastructure, the UnionPay network is expected to provide effective support for the construction and operation of a digital currency system. This study uses the UnionPay network as basis to systematically propose a digital currency information system from three aspects, namely, digital currency account opening, exchange, and use, and further expounds on the operation mechanism of a digital currency information system prototype. This study also discusses how to apply blockchain technology to digital currency, such as using distributed ledger for digital currency confirmation and registration and using blockchain-enabled smart contracts to realize the forward guidance function of the central bank digital currency. Lastly, the current research introduces the value of using the UnionPay network to support the operation of a digital currency information system and its technical challenges, aiming to provide beneficial guidance and reference for future research effort.