Truncated octahedron-like BiOCl: 0.05Eu3+ phosphor was successfully synthesized by a facile hydrothermal method and characterized by X-ray diffraction, scanning electron microscopy, UV–Vis absorption spectra and photoluminescence spectroscopy. Possible morphology evolution mechanism for the truncated octahedron-like BiOCl: 0.05Eu3+ was proposed on the basis of time-dependent experiment. With the prolongation of reaction time, the morphology evolution of the obtained samples from irregular flakes to truncated octahedron-like particles takes place gradually. In addition, the effect of pH value and Eu3+ ions doping concentration on phase, morphology and luminescence property have been further investigated. According to comprehensive analysis of a series of factors like XRD, SEM images and luminescence property, the results shown that the optimum hydrothermal temperature, pH value and Eu3+ ions doping concentration is 160 °C, 6 and 5 mol%, respectively.