The inhibitory effect of extract obtained from destructive distillation of palmyra palm (Borassus flabellifer Linn.) shell on the corrosion of mild steel in 0.5 M H2SO4 and 1 M HCl was investigated using weight loss and electrochemical measurement techniques. The results show that the inhibition efficiency increases with increase of palmyra palm shell extract concentration. The maximum inhibition efficiency in 0.5 M H2SO4 and 1 M HCl was found to be 97.65% and 98.11% for a period of 24 h with 3%v/v concentration of the inhibitor respectively. Thermodynamic parameters were evaluated from temperature studies. Results were fitted into suitable adsorption isotherms. Electrochemical measurements infer that the extract acted through mixed mode of inhibition. Efforts were made to analyze the effectiveness of shell extract of palmyra palm in industrial processes.