The factors that affect intellectual capital creation at firms and how these factors influence the financial performance of firms have been core questions of extant work in the channels of finance for many years. In this period, therefore, the efforts that firms make to increase their intellectual capital to create value and studies that examine the impact of the increased intellectual capital on the firm’s financial performance are notable. Thus, this study aims to explore the influence of intellectual capital and its components on the financial performance of the BIST Sustainability Index companies for the period between 2018:Q4-2024:Q1. A set of Intellectual Value Added Coefficient (VAIC) and its components Human Capital Efficiency (HCE), Structural Capital Efficiency (SCE), and Capital Employed Efficiency (CEE) are employed as indicators of intellectual capital. The financial performance is measured through Return on Assets (ROA) and Return on Capital Employed (ROCE). Control variables included in each model are Market to Book Value (MV/BV), Logarithm of Total Assets (SIZE), and Asset Turnover (ATR). The fixed effects regression results show that an increase in the intellectual capital of the companies listed in the BIST Sustainability Index has a positive effect on their financial performance.