Due to the fact that the waterproofing properties of the waterproofing pigskin leathers are affected by the processing influences, the waterproofing processes and conditions have been optimized and chosen through the investigation into the influences of dyestuffs, retanning agents, fatliquors, finishing agents, etc. on the waterproofing properties of the waterproofing leathers. Results show that the waterproofing properties are good when the pH value is about 6.0 and the static water absorption can be increased when retanning agents are used. The environmental protection requirement is reached when leathers are treated with the waterproofing agents without mineral salts fixing agents.