Depersonalization disorder (DPD) is a dissociative disorder characterized by a subjective sense of unreality and detachment, and has been associated with deficits in perception and short-term memory. In this study, 21 DPD and 17 healthy comparison participants free of psychiatric disorders were administered a comprehensive neuropsychologic battery. The groups did not differ in full-scale, verbal, and performance IQ (Wechsler Adult Intelligence Scale), in working memory (Paced Auditory Serial Addition Test), or in selective attention (Digit Span with Distracters). The DPD group performed significantly worse on immediate visual and verbal recall (Wechsler Memory Scale, Revised), but not on delayed recall. Dissociation severity was significantly correlated with processing slowness and distractibility. We conclude that DPD is associated with cognitive disruptions in early perceptual and attentional processes.