This study provides a comprehensive analysis of the dynamics of fixed capital investment in the Republic of Uzbekistan and develops medium-term forecasts using advanced trend-based econometric approaches. The research examines long-term structural changes, cyclical fluctuations, and growth trajectories in investment volumes based on official macroeconomic time-series data. To ensure methodological rigor, linear, exponential, and polynomial trend models are constructed and comparatively evaluated in terms of goodness-of-fit, statistical significance, and forecasting accuracy. The modeling process incorporates diagnostic testing, residual analysis, and error measurement indicators to enhance reliability and robustness. The findings reveal stable upward tendencies accompanied by periodic volatility driven by structural reforms and external economic factors. Forecast results indicate sustained growth under baseline assumptions, highlighting the strategic importance of investment expansion for industrial modernization and infrastructure development. The study contributes to empirical literature by providing a data-driven framework for investment forecasting and offers practical implications for evidence-based investment policy design, macroeconomic planning, and long-term sustainable economic development.