Abstract: In order to solve the problem of semiconductor laser wavelength drift leading to output wavelength deviation, a dual-loop distributed feedback (DFB) laser two-stage temperature control system was proposed. Based on the internal temperature control system of the semiconductor laser, an external environmental temperature loop control system was introduced to ensure that the laser can operate within a stable temperature range. With an embedded processor as the main controller, a digital proportional-integral-derivative control algorithm was adopted. Combined with pulse width modulation and low-cost H-bridge chips to control the heating and cooling of thermoelectric coolers (TEC), precise control of the laser two-stage temperature was achieved. Temperature stability experiments were carried out by changing the control temperature of the laser while keeping the environmental temperature constant and changing the environmental temperature while keeping the laser operating temperature constant. The results indicate that the temperature control precision of this system can reach up to ±0.03 ℃. Wavelength stability experiments were conducted with a near-infrared DFB laser, and the results showe that the maximum wavelength error of the laser in 120 min is 0.0036 nm. Under constant current conditions, the correlation coefficient between laser output wavelength and temperature is higher than 0.9996. The temperature control system has the characteristics of high precision, low cost and compact size, and has certain application prospects in molecular spectroscopy, gas detection, fiber optics communication, and other fields.