Single crystals of Sm0.55Sr0.45Mn0.4Fe0.6O3 were grown by an optical floating zone technique in an oxygen atmosphere. The powder X-ray diffraction pattern for the grown crystal revealed single-crystalline nature. The lattice parameters and atomic structure were refined and indexed using a General Structure Analysis System (GSAS) to an orthorhombic structure with lattice parameters a = 5.4415 (32) Å, b = 7.6994 (27) Å, c = 5.43868 (28) Å, and space group Pnma. © International Centre for Diffraction Data 2020.