The invention relates to a fox fur tanning agent and a fox fur tanning process thereof. The fox fur tanning agent consists of acrylic acid, diisocyanate, dicarboxylethylamine, azole cyclone, dibutyl itaconate, urea resins, sodium phthalate, o-carboxybenzaldehyde, di-n-butylamine, fatty aldehydes and sodium persulfate. The tanning process comprises the following working procedures of: performing water immersion on fox fur, removing meat, performing softening, performing tanning and performing drying to. The fox fur tanning agent disclosed by invention has favorable tanning effect on the fox fur in a targeted manner. By tanning the fox fur with the tanning agent disclosed by the invention, the working procedures can be effectively simplified; fox leather can be obtained simply by the working procedures of performing water immersion on the fox fur, removing meat, performing softening, performing tanning and performing drying; the tanning working process has fat removing effects on the fox fur; the tanning process is effectively simplified, the tanning efficiency is also effectively improved and the production cost is effectively reduced; and the prepared fox leather has favorable properties of being soft and delicate, wear-resistant, good in elasticity, and the like.