The lightlike geometry of codimension two spacelike submanifolds in Lorentz-Minkowski space has been developed in [15] which is a natural Lorentzian analogue of the classical Euclidean differential geometry of hypersurfaces. In this paper we investigate a special class of surfaces (i.e., marginally trapped surfaces) in Minkowski space-time from the view point of the lightlike geometry.Mathematics Subject Classification (2010). 53A35, 53C50, 83C75.