We present the very first non-collinear magnetic structure calculations of supported metallic 3d triangular trimers. Within the vector Anderson model, in dependence on the ratio between hopping parameters in the trimer the ground state can be collinear or non-collinear. Calculations performed for the Cr and Fe trimers show that the modulus of the magnetic moments per atom are enhanced relatively to bulk value. The dependence, vs. hopping integrals, of the angles between the magnetic moments is different when going from Cr to Fe although these angles are equal to 120 degrees in the ground state of the equilateral triangle.