Fastening part intended to fasten at least one rigid mesh panel consisting of a lattice of vertical and horizontal wires to a fence post comprising, on two opposite sides, a groove for receiving a vertical edge of said mesh panel, each of said grooves comprising a bottom wall and two lateral walls (12, 13) extending opposite to each other substantially perpendicular to the bottom wall, openings (121, 131) being regularly distributed along each of the lateral walls (12, 13) of each of said grooves, the openings (121, 131) of a first of the lateral walls (12, 13) of each said grooves being positioned offset from the openings (121, 131) of the second of said lateral walls (12, 13) in the longitudinal direction of said grooves, said fastening part of said panel on the post being intended to be housed in one of said grooves for receiving the post and to cooperate with the openings (121, 131) of each of the lateral walls (12, 13) of the groove, said fastening part comprising three holding lugs, namely: - on a first edge, first and second holding lugs for holding said panel on said post which are spaced apart and intended to cooperate with two openings (121, 131) of a first of said lateral walls (12, 13) of the groove, and - on a second edge, opposite to the first edge, a third holding lug for holding said panel on said post intended to cooperate with an opening (121, 131) of a second of said lateral walls (12, 13) of the groove, characterised in that said fastening part comprises a plate extended at two of the opposite ends thereof by a wing extending essentially perpendicular to the plate and each intended to bear against the bottom wall of a groove of the post, the third lug extending in the plane of the plate in a first direction, each of the first and second holding lugs extending in the plane of one of the wings in a second direction, opposite to the first direction. said fastening part of said panel on the post being intended to be housed in one of said grooves for receiving the post and to cooperate with the openings (121, 131) of each of the lateral walls (12, 13) of the groove, said fastening part comprising three holding lugs, namely: - on a first edge, first and second holding lugs for holding said panel on said post which are spaced apart and intended to cooperate with two openings (121, 131) of a first of said lateral walls (12, 13) of the groove, and - on a second edge, opposite to the first edge, a third holding lug for holding said panel on said post intended to cooperate with an opening (121, 131) of a second of said lateral walls (12, 13) of the groove, - on a first edge, first and second holding lugs for holding said panel on said post which are spaced apart and intended to cooperate with two openings (121, 131) of a first of said lateral walls (12, 13) of the groove, and - on a second edge, opposite to the first edge, a third holding lug for holding said panel on said post intended to cooperate with an opening (121, 131) of a second of said lateral walls (12, 13) of the groove, characterised in that said fastening part comprises a plate extended at two of the opposite ends thereof by a wing extending essentially perpendicular to the plate and each intended to bear against the bottom wall of a groove of the post, the third lug extending in the plane of the plate in a first direction, each of the first and second holding lugs extending in the plane of one of the wings in a second direction, opposite to the first direction.