The objective of the present study was to perform the cultural adaptation of The Environmental Stressor Questionnaire-ESQ for the Brazilian Portuguese, as well as to verify its reliability and validity. In order to ensure the equivalence between the original instrument and the Brazilian version, all methodological steps recommended in the literature regarding cultural adaptation were followed. The Brazilian version of the ESQ was applied to 106 ICU patients in two hospitals (public and private) in the interior of São Paulo State. Reliability was evaluated in relation to internal consistency and stability (test e retest) and the convergent validity was determined by the correlation between ESQ and generic questions about ICU stress. Reliability was satisfactory with Cronbach's Alfa = 0.94 and stability (ICC = 0.861; IC 95% 0.723; 0.933). ESQ total score displayed strong correlation with the generic questions about stress (r = 0.70; p < 0.0001), thus confirming the convergent validity. The conclusion was that the ESQ adapted for Brazilian culture is a reliable instrument for evaluation of stressors in the ICU.