Inclusion Criteria:  meet the DSM-V diagnostic criteria for schizophrenia; present with prominent negative symptoms with PANSS-negative scores >20, at least one score of PANSS N1-N7 >3, and reductive ratio of PANSS-negative in the past two weeks before recruitment <10%; stable usage and dosage of anti-psychotic medicines in the past two weeks and during the tACS intervention. age within 18-60; illness duration >1year; education at least 6 years; written consent of receiving tACS intervention.  Exclusion Criteria:  Meet any DSM-V diagnostic criteria of any other psychiatric disorders besides schizophrenia ; any history of alcohol or substance dependence in the past 3 months; any other major physical disease (i.e., Sensorimotor disorder, neurological disease); any metal implants or any other tACS contraindication.