**Abstract**

The suitability of *Musa paradisiaca* (banana) peel extract as a green corrosion inhibitor for mild steel in acidic medium (1 M HCl) was investigated using factorial method of the design of experiment. The effects of two independent variables (concentration of banana peel extract and temperature) on the corrosion inhibition efficiency were investigated. The physicochemical properties of the extract such as surface tension, viscosity, flash point, and specific gravity were determined using standardized methods provided by the American System of Testing Materials (D-971). The relationship between the independent variables and the inhibitor efficiency was modeled by gasometric and thermometric methods. The statistical analysis of the inhibition efficiency was carried out using the "Fit Regression Model" of Minitab® 17.0, while the fitness of the models was assessed by the coefficient of determination (R2 ) and the analysis of variance (ANOVA). From the results obtained, gasometric method achieved a maximum inhibition efficiency of 66.83%, with an *R*<sup>2</sup> of 90.76%, whereas thermometric method gave a maximum inhibition efficiency of 65.70%, with an *R*<sup>2</sup> of 95.56%. This study shows that banana peel extract has the capacity to prevent the corrosion of mild steel in acidic medium.

**Keywords:** banana peel extract, biomass, corrosion, inhibitors, factorial design
