Disclosed is a method of reducing smart contract fees for a decentralized application (DApp). A parameter of a request reception event and a public key of a user are stored in a task queue of a computation server. The computation server performs a task requested by the user, calls a state change function for the performed task from a smart contract, and transmits a transaction result to the user when the transaction result is returned. The user pays, to the smart contract, a fee corresponding to the generation of the request reception event, and the computation server pays, to the smart contract, a fee corresponding to a state change of the smart contract. Thus, by minimizing and uniformizing a fee to be paid by a user of a DApp system, it is possible to increase accessibility to a corresponding DApp.