Donna Reiko Kaylila, Ruswan Nurmadi
This research aims to investigate the impact of firm size, liquidity, and sales growth on capital structure, with profitability as a moderating variable among mining sector companies listed on the Indonesia Stock Exchange during the 2019–2023 period. The mining sector was selected due to its strategic role in economic development and its capital-intensive characteristics, which require effective financial management. The study population consisted of 46 mining companies, with 16 companies selected as samples using a purposive sampling technique. The research period covered five years, resulting in a total of 80 observations. Data analysis was conducted using Moderated Regression Analysis (MRA) to examine both direct and moderating effects. The results indicate that firm size and sales growth have no significant effect on capital structure, while liquidity has a significant effect on capital structure. Furthermore, profitability is proven to moderate the relationship between firm size and liquidity toward capital structure, but it does not moderate the effect of sales growth on capital structure. These findings provide insights for financial decision-making in mining companies.