The electromagnetic fields from oblique lightning channel are studied by using FDTD and considering the effects of vertical layered ground conductivity and lightning channel tilt angle. The calculation results show that the initial peak values of lightning electromagnetic fields will increase with increasing the channel tilt angle when the observation point is under the oblique lightning channel, and the rising edges of the electromagnetic fields become steeper. The peak time of the lightning electromagnetic fields will be greater with greater distance between the lightning stroke point on the ground and the observation point. For the electromagnetic fields on the ground surface, the ground conductivity at the same side of the observation point affects mainly the initial peak values of the horizontal electric field and azimuthal magnetic field; the ground conductivity at the other side affects mainly the amplitudes of the wave tail of the horizontal electric field and the azimuthal magnetic field. For the electromagnetic fields inside the ground, the vertical electric field will decrease with increasing the underground depth, but the horizontal electric field and azimuthal magnetic field underground is basically the same as that on the ground surface.