In this paper, we propose a reliability-mechanical study combination to treat the tube hydroforming process (THP). This process consists to apply an inner pressure combined to an axial displacement to manufacture the part. Our goal is the computation of the failure probability of the hydroforming process. Normally, this process is particularly complex and have to be solved numerically. There are several numerical techniques available to compute the solution. However, some design parameters are uncertain and the deterministic solutions could be unacceptable. Thus, a hydroforming process is an important subject for reliability analysis: the finite element method coupled with the first order reliability method (FORM). The definition of the limit state functions takes advantage from the forming limit curve (FLC) used as a failure criterion to detect the occurrence of wrinkling, severe thinning and necking. The THP is completely treated numerically to validate the proposed approach.