With the development of optical storage technology, there is an increasing amount of research based on multi-dimensional high-density storage. Compared to two-dimensional storage, three-dimensional storage can achieve ultra-high-density optical storage by stacking two-dimensional storage layer by layer on the vertical direction. However, three-dimensional storage has problems such as high manufacturing costs, large processing errors and complex readout processes. Therefore, it is of great interest to study the implementation of two-dimensional ultra-high-density optical storage. Plasmonic is one of the most promising technologies to realize ultra-high-density, low maintenance media, and long-life optical storage. In this work, nano-scaled rotary gold square two-dimensional arrays were designed to achieved ultra-high-density optical storage. For angle-resolved localized surface plasmon resonance (LSPR) nano-arrays, when the rotation angle of 1-unit gold square nano-structure is 2°, the storage density was 12.79 GB/cm2, which was 53.29 times of a single-layer Blu-ray disk. By varying the shape and size of the nano-structure, higher two-dimensional storage densities could be achieved. Research results showed that, with proper design, the density of two-dimensional optical storage can match or exceed that of three-dimensional optical storage. This study demonstrates the potential of LSPR-based two-dimensional nanostructures for optical storage, providing another possibility for ultra-high density and high-resolution optical storage.