A method and apparatus for optimizing average bit error probability via a deep multi-armed bandit in an orthogonal-frequency division multiplexing and index modulation system for low power communication are proposed. The method proposed in the present invention comprises: detecting BPSK symbols and subcarriers among all subcarriers; defining a combination of selected subcarriers as a subcarrier selection pattern; selecting the subcarrier selection pattern through learning to minimize the average bit error probability for all combinations of selected subcarriers; and updating a learning parameter of the subcarrier selection pattern selected through learning.