Objective: This study aims to investigate the possible relationship between plasma concentrations of apelin, visfatin and resistin levels of first episode psychosis patients and chronic schizophrenia patients. Methods: A total number of 29 untreated patients with first episode psychosis, 30 chronic schizophrenia and 29 randomly selected weight- and body mass index-matched healthy volunteers were included. The Diagnostic and Statistical Manual of Mental Disorders 4th edition, Positive and Negative Syndrome Scale (PANSS) and Clinical Global Impression Scale were applied to the patient groups. The enzyme-linked immunosorbent assay method was used to measure plasma apelin, visfatin and resistin levels. Results: There was no difference in age, marital status, occupation, and BMI between the groups. Plasma apelin levels were significantly higher in first episode psychosis group than chronic schizophrenia and control group. There was no statistically significant difference in plasma visfatin levels between the groups: first episode psychosis group, chronic schizophrenia and control group. Plasma resistin levels were higher in both first episode psychosis group and chronic schizophrenia group than the control group. There was no statistically significant correlation between plasma apelin and resistin levels and total PANSS scores in the group of patients. Conclusion To our knowledge, this study is the first which investigates the plasma apelin, visfatin and resistin levels in patients with first episode psychosis and chronic schizophrenia. Based on the results of this study, apelin and resistin may be related with some central nervous system pathologies, including the severity of a psychiatric disorder.