The synthesis and structure for the title compound, (C4H12N)[Hg(C7H5OS)(3)], are reported. In the [Hg{S(O)CPh}(3)](-) anion, the Hg-II atom is located at the center of the triangle of S atoms. The Hg-S distances are 2.432(3), 2.442(4) and 2.555(3)A. In addition, there are weak intramolecular interactions between the Hg and carbonyl O atoms [Hg ... O 2.767(7), 2.915 (8)and 3.051(9) Angstrom].