Abnormalities in resting and event-related brain oscillations are known to be associated with cognitive deficits in schizophrenia. Transcranial alternating current stimulation (tACS) modulates these rhythms across the neuronal circuits and could have a potential therapeutic role in psychiatric disorders. In this report, we describe, for the first time, application of online tACS in a schizophrenia patient with working memory deficits. This case report supports the feasibility and potential utility of online tACS in schizophrenia, which needs further systematic research.