Anxiety in schizophrenia possesses specific features and is difficult to assess because no specific evaluating tool is currently available. The aim of this study was to develop and validate a hetero-assessment-based scale to specifically measure anxiety in schizophrenia. A literature review and a survey among psychiatrists allowed the selection of 29 items from 4 previous scales evaluating anxiety. Factor analysis allowed building up a final 22-item composite scale of anxiety evaluation in schizophrenia (SAES), which was then validated in 147 schizophrenic patients. One hundred and forty-seven (147) schizophrenic patients (70.8 % male, mean age = 36.9 years) were included in the study. Principal component analysis of the SAES revealed three factors, namely "expressed and perceived anxiety," "somatic anxiety," and "anxiety and environment". All total and factor scores of the SAES were significantly correlated (p < .001) with total and factor scores of the original scales. Finally, the SAES showed good inter-rater reliability [intra-class correlation coefficient (ICC) = .82]. In conclusion, a specific tool for evaluating anxiety in schizophrenia (SAES) was developed and validated in a sample of schizophrenic patients. The SAES can be useful to investigate clinical, psychopathological, and therapeutic aspects of anxiety in schizophrenia.