A panel joint structure 10 includes: a first panel member 14 that has a first joint portion 14A; a second panel member 16 that is formed of a material having a coefficient of linear expansion different from that of the first panel member 14 and has a second joint portion 16A joined by an elastic adhesive G to the first joint portion 14A; and a projecting portion 18 that is disposed on the second joint portion 16A and contacts the first joint portion 14A to thereby form an interstice S for filling a space between the first joint portion 14A and the second joint portion 16A with the elastic adhesive G.