Background This study evaluated the partial adherence to medication in schizophrenic patients in Korea. Methods The Adherence in Schizophrenia (ADHES) survey was conducted worldwide, including Asian countries. Through questionnaires for clinicians, caregivers and patients, information about medication adherence in patients with schizophrenia and factors affecting adherence were identified. This survey involved 131 psychiatrists from 80 psychiatry clinics and 2824 patients with schizophrenia were enrolled. Results Partial adherence in patients with schizophrenia was prevalent (over 60%) in Korea. From the psychiatrists' point of view, the most prevalent factors associated with partial adherence in their patients were poor awareness of the illness (85%) and embarrassment at having to take medication daily (80%). Psychiatrists believed that most patients (83%) needed help from someone to remind them to take the medication regularly. Of patients, 57% reported feeling upset at having to take medication daily and 76% of caregivers reported preferring long-acting medications. Conclusion Based on the study results, a specific strategy to deal successfully with the prevalent partial adherence to medication in patients with schizophrenia should be developed, and long-acting medication may be one solution to improve partial adherence problems.