Abstract: With the development of domestic semiconductor technology, some domestic components have achieved a performance equivalent to the imported ones, and meet the requirement on performance for nuclear radiation monitoring instruments. In this paper, a set of domestic γ spectrometer was developed based on a 1.5-inch LaBr₃ scintillator. The scintillator, photomultiplier tube and electronic components were all made in China.As the result of testing, the resolution of the spectrometer at room temperature achieved 2.8% at 662 keV. The operating temperature range reached from −40 °C to 50 °C, with an energy resolution better than 3.0% in the whole temperature range.The temperature floating rate for the ¹³⁷Cs all-purpose peak was about −0.67/°C, with a good linearity. The high-voltage adjustment rate was 0.02 V, fulfilling the request for stable spectrum of 0.2 V/°C. The energy non-linearity of the spectrometer was better than 99.99%. The experimental data showed that both the domestic LaBr₃ scintillator, photomultiplier tube, and the electronic components fulfilled the design requirements of γ spectrometer at current stage.