A panel joint structure suppresses stress concentration on a flange corner section-side end-portion of an adhesive during application of a peeling load. A first panel member includes a panel body section, a corner section, and a first flange section. A second panel member is arranged to oppose the first flange section. A joint section joins the first flange section and the second panel member in a contact state thereof, and an adhesive continuously provided in a longitudinal direction of the corner section adheres the first flange section to the second panel member. The first panel member includes a load transmission section near a joint section, and the load transmission section is provided between the panel body section and the first flange section, and an angle θ2 thereof that is defined with the panel body section is larger than an angle θ1 defined by the panel body section and a portion in a short direction of the first flange section. A flange distal end-side end-portion of the load transmission section in the short direction of the flange section is disposed in a region between a corner section-side end-portion and a distal end-side end-portion of the joint section in the short direction of the first flange section.