Natural and biosorbent adsorbents, sourced from agricultural and industrial by-products, have emerged as promising alternatives for the removal of azo dyes from wastewater. These materials, characterized by their abundance, cost-effectiveness, and environmental sustainability, offer significant advantages over conventional treatment methods. This bibliometric analysis investigates 489 publications from 1998 to 2025 indexed in the Web of Science, employing the Bibliometrix package in R for data extraction, analysis, and visualization. The prevailing research focus is on the synthesis, characterization, and performance evaluation of natural and biosorbent materials (e.g., agricultural waste, biomass, mineral clays) for the removal of conventional contaminants such as azo dyes. These materials have been studied for their adsorption mechanisms, including isotherms and kinetics, and their integration into hybrid treatment strategies combining physical, chemical, and biological processes. Moreover, recent studies highlight the exploration of modified adsorbents and nanocomposites to enhance adsorption capacity and efficiency. Despite considerable advancements, challenges remain regarding adsorbent regeneration, scalability, and techno-economic viability. This study provides a comprehensive synthesis of global research trends on natural and biosorbent adsorbents for azo dye removal, offering valuable insights into current progress, thematic evolution, and future directions in sustainable wastewater treatment technologies.