The objective of this study was to assess the construct validity of the Arabic version of mental toughness MT based on the theoretical conception of the MTQ48 questionnaire Clough et al. (2002). The 48 items consist of six components 6C :(1)Challenge CH, (2) Commitment CO, (3)Emotion Control EC, (4)Life Control LC, (5)Confidence in abilities CA,(6)Interpersonal confidence IC ,and the global score MT. The sample consisted of 853 Tunisian participants (444 males and 409 females; 409 athletes and 444 non-athletes), aged 14-27 years (M=20.38 SD=4.12). Cronbach's alpha suggests that over 48 items has adequate internal consistency (α=.72). The EFA revealed a good sampling quality (df = 1128; p < .001). The CFA approved a good model fit (χ²=1146.33; df =1065; CFI=.93; SRMR=.063; RMSEA=.009). In conclusion, our results allowed us to propose a valid Arabic measure of the 6C of MT. The results confirm the factorial validity of the MTQ48 and indicate that the Arabic version of the questionnaire has a robust measure of the psychometric properties of mental toughness. Finally, stakeholders in the Arab region should be able to benefit from the MTQ48 questionnaire, such as and reliable measurement and assessment instruments.