The invention relates to yellowing type oily leather resin for synthetic leather. The resin comprises the following components in parts by weight: 18-30 parts of polyhydric alcohol, 0.5-2 parts of reactive silicone oil, 28-40 parts of isocyanate, 6-10 parts of an alcohol chain extender, 80-120 parts of a solvent, and 2.5-10 parts of an auxiliary agent. The yellowing type oily leather resin for synthetic leather has good thermal viscosity resistance, and embossing post-treatment has good surface brightening effects, hand feeling is unique; the leather produced by the treating agent has natural luster, clear color, good hand feeling, good genuine leather effects, and good general effects.