The invention relates to an titanium-aluminum alloy density gradient material and preparation method thereof. The composition variation between the layers of the titanium-aluminum alloy density gradient material is small, showing gradient change, and a quasi-continuous gradient change is preferable. The preparation method comprises the following steps of: taking Ti6Al4V powder and AlSi10Mg powderas a raw material, adopting a coaxial real-time variable-ratio powder feeding method, gradually changing the components of the titanium alloy and the aluminum alloy powder, melting the metal powder byusing a high-power laser beam, and manufacturing the metal powder by layer-by-layer superposition. The titanium-aluminum alloy has the advantages that: the composition variation between the layers ofthe titanium-aluminum alloy density gradient is small, showing gradient change, and the material property (such as hardness) in the thickness direction is change in gradient, and the gradient material with complex shape can be prepared. The titanium - aluminum alloy density gradient material is a low-density material, and can meet the light and high-strength requirements of materials in the fields of aerospace, automobile manufacturing and the like, and has important theoretical and practical application values.