This report analyzes the relationship between ownership structure and firm performance using TOBIN_S_Q as the dependent variable. The report includes descriptive statistics, correlation analysis, and regression analysis. The impact of control variables such as LONG_TERM_DEBT, MARKET_VALUE, NET_PROFIT, and TOTAL_ASSET on TOBIN_S_Q is also explored. The study is based on a sample of 995 observations from 199 cross-sections. The findings suggest that ownership structure has a significant impact on firm performance.