The aim of this work consist to compare the traditional viscoelastic material models vs the fractional ones, determinate the fractional order of the differential operator that characterize the mechanical stress-strain relation, the stress relaxation and the creep compliance of this models for a biological soft tissue, in particular a femoral artery. Apply the Laplace transform for Mittag-Leffler function type and the convolution on fractional standard lineal solid differential equation, known as Zener model, to obtain analytical solution. Simulated the force-pressure related by singular blood flow pulse and the displacement response.