Despite a wide phenomenological interest in body image pathology in schizophrenia, there has been little systematic empirical research. This study aimed at establishing the specificity of body image pathology in patients with schizophrenia, its changes during acute treatment, and its association with other symptom factors. Cognitive (thoughts/beliefs regarding the body--body concept), affective (body satisfaction--body cathexis) and perceptual (body size estimation--body schema) facets of body image and psychopathology were assessed in in-patients with paranoid schizophrenia (N = 60), schizoaffective disorder (N = 19), depressive disorder (N = 40) and anxiety disorder (N = 28) at admission, and after 2 and 4 weeks of treatment. Body size perception was also assessed in a sample of healthy subjects (N = 44). Patients with paranoid schizophrenia/schizoaffective disorder showed under-estimation of lower extremities at each time point. They expressed a higher degree of body concept disturbances at admission, but not at later stages. In a factor analysis, body perception and body concept loaded on distinct factors, which were separate from positive symptoms, negative symptoms, and anxiety. Patients with acute paranoid schizophrenia and schizoaffective disorder seem to have a specific and consistent disturbance of body size perception, which might indicate a dysfunction of sensory information processing.