Teamwork training and evaluation are essential to enhance safety and quality of care. The lack of the psychometric testing of the TeamSTEPPS® Teamwork Attitudes Questionnaire (T-TAQ) and Teamwork Perceptions Questionnaire (T-TPQ) across different language and cultural settings has questioned their widespread use because such attitudes and perceptions are highly subjective and context-bound. The present study aims to translate the T-TAQ and T-TPQ into the French language and validate the psycho- metric properties of the two questionnaires in a public health context. A forward-backward translation process, panel reviewing, and pilot testing in two rounds were followed to develop the French versions. Confirmatory factor analysis (CFA) and Cronbach’s alpha were used to examine the factor structure and internal consistency, whereas two-way mixed Intraclass Correlation Coefficient (ICC) was performed to assess test-retest reliability. A total of 235 healthcare professionals in the French-speaking community of Belgium completed the T-TAQ and T-TPQ. After two to four weeks, 102 participants took part in the second round. Despite good fit indices as revealed by the CFA and Cronbach’s alpha from 0.53 to 0.75 for the five dimensions of the T-TAQ and 0.76 to 0.79 for the T-TPQ, the squared correlations among the constructs were higher than the average variance extracted. Two-way mixed ICCs indicated fair to good test-retest reliability for all the five constructs of the two questionnaires, except the leadership scale of the T-TAQ. The French-language versions of the T-TAQ and T-TPQ were semantically equivalent and culturally relevant with adequate test-retest reliability as compared to the English versions. These two instruments might be used to capture the overall attitude toward teamwork and perceptions of team skills and behaviors. Yet, further research is advisable to refine the scales to establish the discriminant validity of the different dimensions and discriminative power of the instruments.