The invention discloses a diabetic foot treating nano-level pharmaceutical composition and a preparation method thereof. The diabetic foot treating nano-level pharmaceutical composition is prepared from dichocarpum dalzielii, rhizoma dioscoreae tokoro, canthium horridum blume, rhizoma kaempferiae, panzeria alashanica, sageretia root, radix loropetalum chinense, potentilla bifurca, catechu, lycopodium clavatum, fructus piperis longi, rhizoma matteucciae struthiopteris, radix clematidis, herba lysimachiae, sedum amplibracteatum, stellaria media, purple lythrum extract, sedum aizoon extract, zinc oxide powder with particle size ranging from 50 nanometers to 100 nanometers, titanium dioxide powder with particle size ranging from 50 nanometers to 100 nanometers, sodium hydroxide powder with particle size ranging from 50 nanometers to 100 nanometers, seawood meal powder with particle size ranging from 50 nanometers to 100 nanometers, salicylic acid, vitamin E and vitamin C. Based on the traditional Chinese medicine theory that treating internal illness by external treatment according to both symptoms and root causes, the pharmaceutical composition has functions of diminishing inflammation, detoxifying, clearing stasis and promoting granulation to symptoms of diabetic feet, further prompts complete healing of gangrenous wounds while keeping regenerated skin smooth and flat without obvious scars, and is mild in property without any side and toxic effects.