The invention relates to a corner structure (16) for a leaktight and thermally insulating tank for storing a fluid, comprising a plurality of walls (1, 101, 201); the said corner structure (16) being intended to be arranged in a corner between a first wall (101) and a second wall (201) and comprising:



a first angle bracket (32) anchored to an anchoring device (16) intended to be fastened to the supporting structure (3) of the first and second walls (101, 201);
the anchoring device (16) comprising a first tab (18) and a second tab (19) intersecting one another, each of the first and second tabs (18, 19) comprising an external portion (24, 25) and an internal portion (22, 23) which are arranged on either side of an intersection between the first tab (18) and the second tab (19);
the corner structure (16) furthermore comprising a first insulating panel (42) which is arranged in a first space delimited by the internal portion (22) of the first tab (18) and the external portion (25) of the second tab (19), and a first lateral insulating packing element (48) which is compressed between the first insulating panel (42) and the external portion (25) of the second tab (19).