In this study, theoretical analysis and experimental investigation of the temperature characteristics of a 974 nm dual-fiber Bragg grating laser are conducted. The effect of grating pitch on reflectivity is theoretically simulated. First, the spectrum of the device is measured at room temperature (25 ℃). Compared with the spectrum of a device without a dual-fiber grating, the secondary peak in the spectrum of the dual-fiber grating laser is significantly suppressed, and the peak wavelength (974.07 nm) of the test laser is locked near the center wavelength of the grating at 974 nm. The power current voltage characteristics characteristics of the device are also measured. When the operating current reaches 400 mA, the output power of the pigtail is greater than 253 mW. Then the wavelength change rate and power change rate of the device at full temperature are analyzed, and it is found that the wavelength change rate is less than 8.2×10 -3 nm/℃. Finally, the differential structure function curve of the device is obtained, and the thermal resistance distribution is analyzed. By optimizing the heat sink sintering process, a device power change rate of less than 1.06% is obtained.