A joint filling profile for forming a joint sealing between floor slabs includes a vertical leg projecting into the joint and a profile body formed from a joint sealing compound and located in a joint widening. The vertical leg and the profile body are separated from each other with the interposition of a first separating material, wherein at least one second separating material is arranged between the vertical leg and the profile body and/or at least one reinforcing mat is arranged within the profile body. The second separating material and/or the reinforcing mat are arranged in such a way that they overlap with the first separating material at least in regions.