Natural asphalt is a highly valuable material with diverse uses that humans have been utilizing for centuries. Its beneficial qualities, environmental friendliness compared to synthetic alternatives, versatility, and cost-effectiveness contribute to its overall importance as a valuable natural material. It emphasizes the abundance and significance of Iran’s natural asphalt, which is known to be one of the largest producers globally. The investigations of the characteristics and analysis methods provide valuable information for further research and utilization in various industries, particularly in road construction and maintenance. The chapter utilizes several analysis methods, including Fourier Transform Infrared (FT-IR), elemental analysis, X-ray fluorescence, thermogravimetric analysis (TGA), and scanning electron microscope (SEM) analysis, to investigate the characteristics of Iranian natural asphalt. These techniques help understand its composition, thermal stability, and properties relevant to its application as a filler and bitumen modifier in asphalt mixtures and it explains how it improves various properties of traditional bitumen, enhancing stability, durability, rutting resistance, and water resistance. This is due to its exceptional traits such as high viscosity, thermoplastic behavior, and robust adhesive properties, making it a valuable modifier and filler in the industry.