The flow of viscoelastic fluids through micro/nanofluidic systems is an important issue in the biological applications. The electrokinetic effects on pressure driven flow of a viscoelastic fluid through a nanochannel with slip boundary condition are investigated in this study. The rheological behavior of the viscoelastic fluids is described using constitutive equations and the linear Navier's law is employed to consider the slip condition on the channel walls. The Debye–Hückel linearization is employed to obtain a closed form analytical solution for the velocity distribution and induced electric field as function of slip parameter, Reynolds number, viscoelastic parameter, dimensionless Debye–Hückel parameter and dimensionless zeta potential. It is found that the induced electric field increases with increasing both dimensionless zeta potential and dimensionless slip coefficient while it decreases with increasing dimensionless Debye–Hückel parameter.