A new barium potassium phosphate fluoride K2BaPO4F has been successfully synthesized by solid-state reaction. Single-crystal X-ray diffraction analysis reveals that it crystallizes in tetragonal space group of 14/mcm with a = 7.026(1) angstrom, b = 7.026(1) angstrom, c = 11.279(4) angstrom, V = 556.8(2) angstrom(3), and Z = 4. The structure consists of the [PO4] tetrahedral groups (A-site) and the F-centered octahedral [FK4Ba2] groups (B-site), which link together through vertices to form the perovskite-type framework and can be represented as ABX(3). The UV-Vis-NIR spectrum shows that K2BaPO4F possesses a short cut-off wavelength below 190 nm, which indicates that it may be applied in the deep-UV region. The calculated band structures and the density of states based on first-principles calculations indicate that K2BaPO4F is an indirect band gap compound. In addition, IR spectroscopy and thermal stability of K2BaPO4F are also reported in this work.