An outdoor solar lamp assembly structure includes a base having a receiving slot, a translucent lamp cover covering on the top and outer periphery of the base, and a solar lighting module installed between the base and the translucent lamp cover, and a waterproof design is provided between the translucent lamp cover and the base, and the solar lighting module has a multiple of LED lamps, a solar panel, and a battery integrated and installed onto both front and back sides of a circuit board with a modular design which is conducive to assembly and maintenance.