An apparatus and a method of realizing an antenna matching in accordance with a user's body effect and a state of a mobile device are provided. The method includes determining a state of the mobile device on a basis of a call mode and at least one of whether an external device is connected to the mobile device, whether a receiver is being used, whether a speaker is being used, and whether a proximity sensor is activated, determining an optimal Tunable Matching Network (TMN) circuit adjustment value in accordance with the determined state, and performing the antenna matching in accordance with the optimal TMN circuit adjustment value.