The mixed (1:1:1) adduct between SbF3,1,10-phenanthroline, and thiourea has been prepared. The compound has been characterized via Mössbauer spectroscopy and X-ray analysis on a single crystal. It crystallizes in the triclinic space group P1 with a = 7.736(1), b = 10.443(1), c = 10.509(1) Å, α = 92.3(1), β = 108.9(1), γ = 111.1(1)°, and Z = 2. The structure was solved by Patterson and Fourier methods; full-matrix least-squares refinement based on 3 340 observed reflections gave a final R = 0.026 (R′ = 0.030). The distorted octahedral co-ordination polyhedron is characterized by very asymmetrical bonds to the central ion [Sb-F(1) 1.938(2), Sb-F(2) 1.997(2), Sb-F(3) 1.948(2), Sb-N(1) 2.556(3), Sb-N(2) 2.731(3) Å] and by a relatively short Sb ⋯ S interaction of 3.061 (3) Å. The whole structure is held together by intermolecular hydrogen bonds.