The title salt, C8H11N2O(+)·Br(-), was synthesized by the reaction between 4-meth-oxy-benzamidine (4-amidino-anisole) and hydro-bromic acid. In the cation, the amidinium group has two similar C-N bonds [1.304 (2) and 1.316 (2) Å], and its plane forms a dihedral angle of 31.08 (5)° with the benzene ring. The ions are associated in the crystal into a three-dimension hydrogen-bonded supra-molecular network featuring N-H(+)⋯Br(-) inter-actions.