ABSTRACT Background: Use of internationally standardized instruments to assist healthcare professionals in accurately recognizing stroke early is recommended. The process of translation and cross-cultural adaptation is important for ensuring that scales are interpreted in the same way in different languages, thus ensuring applicability in several countries. Objective: To translate into Brazilian Portuguese, cross-culturally adapt and validate the Cincinnati Prehospital Stroke Scale, using a representative sample of the Brazilian population. Method: The present study included patients with suspected stroke who were treated at a Brazilian emergency medical service and referred to a stroke center. A systematic process of translation and cross-cultural adaptation of the original scale and application of the final instrument was performed. Statistical analysis was used to assess the sensitivity, specificity and accuracy of the scale. Cohen’s kappa coefficient was used to assess inter-rater reliability. Results: After translation and cross-cultural adaptation, the scale was applied to 64 patients. It showed 93.0% accuracy and 92.4% sensitivity in relation to the final “gold standard” diagnosis. Cohen’s kappa coefficient was calculated using data from 26 patients (40.6%) and showed excellent inter-rater reliability between items on the scale (0.8385 to 1.0000). Conclusion: The scale demonstrated excellent accuracy, sensitivity and inter-rater reliability. It was a useful tool for assisting healthcare professionals during initial assessments on patients with suspected stroke and significantly contributed to early recognition of stroke in a simple and quick manner.