In this paper, lightning electromagnetic fields in the presence of an ocean-land mixed propagation path having different configurations are evaluated using a finite-element-based full-wave approach. The simulations are conducted considering lightning strikes to ground and to the ocean. The lightning electromagnetic fields are obtained for observation points inside the ground and on the ground surface. The land-ocean interface is represented by a linearly increasing ocean depth characterized by the slope angle. Different sets of simulation results show that the electric field components (vertical and horizontal) in the immediate vicinity of the interface can be affected by the interface slope angle. The obtained results also show that, for observation points located beyond 50 m or so from the ocean, the effect of the slope angle of the ocean-land interface on the lightning electromagnetic fields can be disregarded.