The invention discloses anion organ silicone mulsion leather slip agent and a preparation method thereof. Most of the prior organ silicon leather slip agent is only provided with amino group and difficult plays the function of durability. The invention adopts anion emulsifier sodium dodecyl benzene sulfonate and nonionic emulsifier fatty alcohol polyoxyethylene ether and takes benzene sulfonic acid as catalyst; the emulsion copolymerization is performed to the coupling agent containing crosslinking functional group, the coupling agent containing amino-hydrocarbon and the organ silicon monomer to prepare anion organ silicon emulsion. The organ silicon emulsion contains sulfhydryl or epoxy group crosslinking functional group and simultaneously contains the amino-hydrocarbon functional group, the slip agent is ensured to have durability by the crosslinking functional group and is ensured to meet the requirements of slipperiness, lubrication and waterproof by the amino-hydrocarbon.