A Lorentzian para-Sasakian manifold M$(varphi, zeta, eta, g)$ (abr. LPS-manifold) has been defined and studied in [9] and [10]. On the other hand, para-Sasakian (abr. PS)-manifolds are special semi-cosympletic manifolds (in the sense of [2]), that is, they are endowed with an almost cosympletic 2-form $Omega$ such that $d^{2eta}Omega = psi(d^omega$ denotes the cohomological operator [6]), where the 3-form $psi$ is the associated Lefebvre form of $Omega$ ([8]). If $eta$ is exact, $psi$ is a $d^{2eta}$-exact form, the manifold M is called an exact Ps-manifold. Clearly, any LPS-manifold is endowed with a semi-cosymplectic structure (abr. SC-structure).