The aim of this study was to explore memory deficits and psychopathology and their relationships with P300 in drug-naïve patients with schizophrenia. The Positive and Negative Syndrome Scale (PANSS) and the Wechsler Memory Scale—Revised were administered. Auditory event-related potentials elicited by an oddball paradigm were obtained. After controlling for age, sex, the results showed a statistically significant negative correlation between the total PANSS score and P300 amplitude at the parietal position (r = −0.66, p