Abstract: In recent years, the macro economy continues to decline, the supply-side reform continues to deepen, the cost supervision and examination has become increasingly strict, and the power grid companies are faced with problems such as narrowing profit space and continuously increasing operating pressure. It is urgent to change the cost management mode, refine the granularity of cost management, and promote lean equipment management. This article explores the collection and allocation rules of substation and transmission line costs based on financial multidimensional data. Firstly, the three maintenance costs are directly linked to specific station lines through work orders and projects, and costs that cannot be clearly linked are allocated and processed. Secondly, specific descriptions and formula definitions were provided for the quantification and aggregation of labor costs and other operating expenses. Furthermore, the differences in cost investment in substations were explored from different perspectives, and multiple linear regression models were used to analyze their influencing factors. It was found that factors such as substation scale, equipment status, and layout methods all have an impact on substation production costs. Finally, the article concludes that this study provides a powerful tool for accurately grasping the operation and maintenance costs of station lines, but the standardization and completeness of basic data still need further optimization.