First and second engaging members (15) each including an engaging portion (15n) are attached to a ridge-side end of each of first through third solar cell panels (11) and are disposed with an interval in a beam direction. First and second engaged members (21) each including an engaged portion (21i) are attached to an eaves-side end of each solar cell panel (11) and are disposed with an interval in the beam direction. The engaging portion (15n) of the first engaging member (15) of the first solar cell panel (11) is engaged with the engaged portion (21i) of the first engaged member (21) of the second solar cell panel (11), whereas the engaging portion (15n) of the second engaging member (15) of the first solar cell panel (11) is engaged with the engaged portion (21i) of the second engaged member (21) of the third solar cell panel (11).