Abstract Objective To describe the cross-cultural adaptation of the Anger Rumination Scale (ARS) for use in Brazil. Methods The cross-cultural adaptation followed a four-step process, based on specialized literature: 1) investigation of conceptual and item equivalence; 2) translation and back-translation; 3) pretest; and 4) investigation of operational equivalence. Results A final Brazilian version of the instrument (ARS-Brazil) was defined and is presented. Pretest results revealed that the instrument was generally well understood by adults as well as indicated a few modifications that were included in the final version presented here. Conclusion The Brazilian Portuguese version of the ARS seems to be very similar to the original ARS in terms of conceptual and item equivalence, semantics, and operational equivalence, suggesting that future cross-cultural studies may benefit from this early version. As a result, a new instrument is now available for the assessment of rumination symptoms of anger and irritability for adults in community, clinical, and research settings.