Provided is a coaxial electrospinning multi-jet spray head for preparing a composite fiber membrane. The coaxial electrospinning multi-jet spray head is provided with multiple controllable inorganic solution injection devices, multiple controllable organic solution injection devices, a controllable gas supply device, gas flow channels, metal solution dividing flow channels achieving uniform organic spinning solution delivering, a sheath gas hole array, an auxiliary gas outlet, a high-voltage power supply capable of independently supplying power, a receiving device, a spinning spray head assembly, a second-level gas flow buffer cavity, buffer chambers, a clamping plate, inorganic solution inlets, a first-level gas flow buffer chamber, solution dividing flow channels achieving uniform inorganic spinning solution delivering and solution distributors. Accordingly, respective uniform mixed jetting of an organic solution and an inorganic solution can be achieved, the solution supply uniformity of all the spinning spray heads can be improved, and the repulsive interaction among jet flows is weakened; in addition, the large-scale production demands of nano-composite materials are met by adjusting the solution supply speed and the weight ratio of the organic solution and the inorganic solution.