In order to improve the synthesis performance of 3，3′-diamino-4，4′-azoxyfurazan （DAAF） by conventional methods， broaden the synthetic pathway of DAAF. A microfluidic reaction system was designed to synthesize DAAF using 3，4-diaminofurazan （DAF） as the main raw material by microfluidic technology. Orthogonal experiment was designed to optimize the synthesis conditions. DAAF with a purity of 99.33% and a yield of 89.96% was synthesized at 25 ℃， a flow rate of 4 mL·min^-1 and a length of 5 m in the outlet crystallizer. The structure of the synthesized product was characterized by infrared， nuclear magnetic and elemental analysis， and was characterized by scanning electron microscope （SEM）， X-ray diffraction （XRD）， thermal analyzer （DSC/TG） and mechanical sensitivity. The results show that DAAF was clustered flower ball with an average particle size of 5.36 µm； Microfluidic synthesis has no effect on the crystal structure of DAAF. At the heating rate of 10 ℃·min^-1， the thermal decomposition peak temperature is 262.36 ℃， and the mass loss rate during thermal decomposition is 82.79%. The mechanical sensitivity test shows that the impact sensitivity is 90 J， and the friction sensitivity is 0%. Compared with the DAAF synthesized by the conventional method， the average particle size decreased by 7.36 µm， the particle size distribution is uniform and the particle size distribution range is narrowed， the crystal structure does not change， the thermal decomposition peak temperature was advanced by 9.57 ℃， the mass loss rate was reduced by 6.99%， the impact sensitivity is increased by 5 J， and the safety performance is improved.