A crude oil containing high paraffin from Yanchang Oilfield was studied for the situ waxing inhibition as an example in this work. The components were separated using silica gel column chromatography by different eluent and were named A1 to A14, and the characteristics of each component and their influence on wax crystallization were studied. It was found that the separated components could interact with each other to decrease the temperature of the wax point to 0.2-1.64 degrees C, but the effect on the amount of wax was relatively small. Polarized micrographs showed that the components also affect the morphology and distribution of the wax crystals. For example, the component A5 make the wax crystals of A1 larger and make the distribution of wax crystals in a certain direction and more dispersed.