Bio-asphalt has emerged as a strategic solution for reducing the environmental footprint of pavement infrastructure by partially replacing petroleum-based binders with renewable biomass-derived resources such as bio-oil, lignin and agricultural by-products. Despite the rapid growth of experimental studies, a consolidated understanding of the intellectual evolution, performance-oriented research directions, and implementation challenges of bio-asphalt remains limited. This study presents a systematic bibliometric and performance-integrated review of 343 Scopus-indexed publications published between 1995 and 2025 to map the global development of bio-asphalt technologies. The results reveal an exponential increase in research output after 2015, driven by sustainability mandates, circular-economy initiatives, and advances in biomass conversion technologies. Science mapping indicates a clear thematic transition from early material substitution toward performance-oriented research focusing on rheology, durability, aging resistance, and hybrid modification strategies. A persistent performance imbalance between high-temperature rutting resistance and fatigue or low-temperature cracking resistance is identified as a central design challenge. Bio-oils are primarily used to enhance workability, rejuvenation efficiency, and cracking resistance, whereas lignin, polymers, and nanomaterials are increasingly incorporated to restore stiffness and mitigate rutting susceptibility. By integrating bibliometric analysis with engineering performance synthesis, this study identifies key research gaps and proposes a framework for the development of balanced, durable, and low-carbon bio-asphalt systems.

bio-asphalt, bibliometric analysis, performance balance, rutting resistance, cracking resistance, sustainable pavements