The invention belongs to the field of building materials, and particularly relates to a wood floor protective agent and a preparing method thereof. The wood floor protective agent is prepared mainly through following raw materials including, by weight, polyvinyl formal, chionanthus retusus fruit oil, live oak leaves, sapium sebiferum oil, hibiscus, ethylparaben, amino acetic acid dihydroxyaluminumsalt, chlorinated paraffin, phenoxyethanol and pistacia weinmannifolia oil. The hibiscus, the live oak leaves, the phenoxyethanol, the pistacia weinmannifolia oil, the chionanthus retusus fruit oil and the sapium sebiferum oil, all of which have an anti-bacteria function are added in the wood floor protective agent, the chlorinated paraffin, the amino acetic acid dihydroxyaluminum salt, the ethylparaben and the polyvinyl formal, all of which have the protection function on the wood floor are added, accordingly, the anti-dirt performance of the wood floor can be improved, bacterium germinationof the wood floor is reduced, wood floor installing and using are convenient, the original color of the wood floor can be kept as well, and the service life of the wood floor is prolonged.