Novel compound, Sr₃Bi₂(BO₃)₄, and Sr₃Bi₂(BO₃)₄:Eu³⁺ series were firstly synthesized by crystallization from a melt. The crystal structures of Sr₃Bi₂(BO₃)₄ and Sr₃Bi_1.66Eu_0.34(BO₃)₄ borates were refined from single crystal X-ray diffraction data to R₁ = 0.051 and 0.067, respectively. Sr₃Bi₂(BO₃)₄ borate crystallizes in the orthorhombic space group Pnma, a = 7.5107 (5), b = 16.2737 (11), c = 8.8163 (5) Å, V = 1077.59 (12) ų, Z = 4. These compounds are isotypical to those of A₃REE₂(BO₃)₄ family, A = Ca, Sr, Ba. Crystal structure consists of isolated BO₃ triangles and three independent M1O₈, M2O₈ and M3O₈ polyhedra, which are connected by corners and edges forming the framework. The distribution of Sr and Bi atoms is partially disordered over M1-M3 positions. Thermal transformations of Sr₃Bi₂(BO₃)₄:Eu³⁺ series were studied by DSC and TG, powder HTXRD, thermal expansion of Sr₃Bi₂(BO₃)₄ borate was investigated by powder HTXRD. The emission spectra of Sr₃Bi₂(BO₃)₄:Eu³⁺ show characteristic lines attributed to the intra-configurational 4f-4f transitions in Eu³⁺ ions. Sr₃(Bi_0.85Eu_0.15)₂(BO₃)₄:Eu³⁺ demonstrates the strongest luminescent intensity among studied in this work borates. It can be concluded that Sr₃Bi₂(BO₃)₄:Eu³⁺ is a promising red phosphor.