Abstract New ternary silicides RERhSi (RE=Y, Gd, Tb, Dy, Ho, Er) have been prepared by arc melting from the elements and annealed for for several days at 800°C. Single crystal studies show these materials to be of orthorhombic symmetry and isostructural with TiNiSi (anti-PbCl 2 structure). Gd, Tb and Dy compounds show a spontaneous magnetization and their ordering consists probably of a non-colinear arrangement of the moments. HoRhSi and ErRhSi order antiferromagnetically at 8K and 7.5K respectively. At 4.2K HoRhSi undergoes a metamagnetic transition above 6kOe. A field transition appears also at 4.2K for ErRhSi above 12kOe.