AbstractThe present investigation was aimed at exploring the anticorrosive behavior of bio‐organic Auraucaria heterophylla gum exudate (AHGE) on mild steel (MS) corrosion in 1 M phosphoric acid solution by weight loss technique, electrochemical studies, and computational analysis. Additionally, the performance was analyzed by morphological and quantum chemical analyses. The weight loss data revealed that AHGE showed 80% of inhibition efficiency at 303 K temperature. Inhibitor adsorption on MS was in line with Langmuir and Tempkin adsorption isotherms. Potentiodynamic studies showed that the investigated AHGE performed as a mixed‐type inhibitor. Electrochemical parameters like charge transfer resistance, double‐layer capacitance, and inhibition efficiency were determined and presented. Results obtained through computational analysis, scanning electron microscopy/energy dispersive X‐ray analysis, and atomic force microscopy studies were well supported by the inhibitive potential of AHGE.