Abstract: High and low voltage cables in distributed photovoltaic power generation projects are still mostly copper core cables, while aluminum alloy cables are rarely used. The cost of cables accounts for about 2%-3% of the investment cost of the entire photovoltaic system. The proportion is relatively small. However, under the influence of policy document No.531, the electricity price subsidy has been continuously reduced. The profits of photovoltaic enterprises will be affected. In addition, the industry competition is increasingly fierce, and the industry has entered the era of meager profits. Photovoltaic enterprises must accelerate the system cost reduction from an all-round perspective of the project, so as to meet the industry's requirements for parity grid connection of photovoltaic power generation (similar to the grid connection price of desulfurization coal-fired units). Based on practical cases, this paper analyzes the economic advantages of replacing copper core cables with aluminum alloy low-voltage cables on the basis of technical feasibility, and provides a reference for subsequent cost reduction and efficiency increase and scheme optimization.