Using by the method of one step Ag and Cu dual elements based Metal Assisted Chemical Etching(MACE), a nano-light trapping structure was prepared at a room temperature on the surface of the multicrystalline silicon. Then, the silicon wafers were made an anisotropic refactoring using by a Nano Structure Rebuilding (NSR) solution at a temperature of 50℃, so that the invert pyramid light trapping structures with different sizes were prepared. The reflectance and surface morphologies of multicrystalline silicon, and the minority carrier lifetime of the passivated multicrystalline silicon were measured by spectrophotometer, scanning electron microscopy and Sinton WCT-120 tool respectively. The results show that, the main factor to affect the final size of invert pyramid structure is the depth of the as-etched nanostructure. The deeper the depth is, the larger the final size of invert pyramid structure becomes. With the increase of NSR refactoring time, the size of the invert pyramid structure goes larger and the reflectance becomes higher too. While the minority carrier lifetime increases with the increasing of the size of invert pyramids after atomic layer deposition passivating, one should make a balance between anti-reflection result and passivation effect. An invert pyramid with an edge length of 600 nm is found to be an optimal size, corresponding a reflectance of 9.87% and a minority carrier lifetime of 37.82 μs.