In this paper, we study invariant, slant and screen slant lightlike submanifolds of indefinite para-Sasakian manifolds. We obtain necessary and sufficient conditions for existence of slant and screen slant lightlike submanifolds of indefinite para-Sasakian manifolds and also provide non-trivial examples of such submanifolds. We obtain integrability conditions of distributions $D$ and $RadTM$ on screen slant lightlike submanifolds of indefinite para-Sasakian manifold. Further we obtain sufficient condition for induced connection on screen slant lightlike submanifolds of indefinite para-Sasakian manifold to be metric connection.