The invention belongs to the technical field of lubricant preparation, and particularly relates to lithium-based lubricating grease containing nano-particles and a preparation method thereof. The lithium-based lubricating grease containing the nano-particles is prepared from, by weight, 97%-99% of general lithium-based lubricating grease, 0.5%-1.5% of nano SiO2 and 0.5%-1.5% of nano MoS2. The preparation method comprises the steps that the general lithium-based lubricating grease, the nano SiO2 and the nano MoS2 are weighed by weight; the nano SiO2 and the nano MoS2 are ultrasonically dispersed into ethyl alcohol; the dispersed nano SiO2 and nano MoS2 and the ethyl alcohol are together added into the general lithium-based lubricating grease, even mixing is performed, and then the finished product is obtained. According to the lithium-based lubricating grease containing the nano-particles and the preparation method thereof, the general lithium-based lubricating grease serves as a criterion, the nano SiO2 and the nano MoS2 particles are added, and therefore the lubricating grease obtained through modification is better in wear resistance and higher in carrying capacity.