Novel complexes of Sb(III) fluorides with cation of β-aminopropionic acid (β-alanine), (NH3(CH2)2COOH)SbF4 ⋅ H2O (I) and (NH3(CH2)2COOH)SbF4 (II), are synthesized and their crystal structures are determined. Crystals I and II are monoclinic with a = 12.1580(5) Å, b = 7.4167(4) Å, c = 10.1540(5) Å, β = 108.222(2)°, Z = 4, space group P21/c for (I) and a = 10.483(1) Å, b = 7.5906(8) Å, c = 9.4237(9) Å, β = 90.548(2)°, Z = 4, space group P21/c for (II). Structures I and II are formed by β-alaninium cations (C3H8NO2)+ and complex anions [SbF4] n n− with polymer chain structure. Complex I also contains crystallization water molecules. In the structures of complexes I and II, the β-alaninium cations have different conformation, the torsion angles C(1)C(2)C(3)N in these complexes are 174.5° and 77.0°C, respectively.