The anchoring device for a cable made of plurality of tendons comprises an anchor block having a front side, a rear side and channels extending between the front and rear sides, each tendon of the cable being received in a respective channel with a blocking member. It also comprises a first protective material with which at least some of the channels of the anchor block are filled, a chamber containing portions of the plurality of tendons of the cable, located on at least one of the front and rear sides of the anchor block, and a second protective material, different from the first protective material, with which the chamber is filled.