A roof panel abutment structure is disclosed. The structure comprises: a roof frame, a first roof panel having one end coupled to the roof frame, the one end formed in a shape in which a recess is inserted between a pair of ridges on a cross-section thereof; a bolt fastened to the recess portion to fix the first roof panel to the roof frame; a second roof panel having an opposite end thereof coupled to one end of the first roof panel; a first adaptor having a base and a wing portion connected to both sides of the base, wherein the base is fixed to the recess portion by means of the fastening of the bolt, and the wing portion is coupled to both sides of a T groove, a second adaptor formed in a shape corresponding to the shape of the T groove, a clamp installed such that a bottom is coupled to the second adaptor, and a solar panel coupled to the clamp and installed to cover the roof panel. The roof panel abutment has increased strength, and even if a portion of the roof panel is deformed, the upper panel is not disengaged so as to maintain the abutment structure.