A discharge grille of an intermediate casing of a turbomachine includes a peripheral edge and a seal mounted on the peripheral edge via an attachment system, the seal ensuring the sealing between a first turbomachine member and a second member of the turbomachine, and surrounding the discharge grille of the intermediate casing, the seal having a U-shaped cross section and includes a base plate configured to bear against the first member, a sealing lip configured to bear against the second member through deformation of the sealing lip to ensure air tightness and fire proofing through contact.