Factorial Design on the Corrosion Inhibition Effects of Rubber Seed Oil on Mildsteel was conducted in this study. The inhibitor concentration, reaction time and temperature were considered, to assess their individual and combined effects on the corrosion inhibition efficiency using standard (statistical) means. The Chochrain’s distribution, G for the study sample was computed to be 0.2594, while the observed one, GTable is 0.6798 at 0.05 level of significance. Also, the Fcalculated was found to be 292.6066, while the Ftable is 4.46. By these values of ‘G’ and ‘F’ (calculated and observed), it was, respectively, deduced that the hypothesis for the homogeneity of variance is acceptable and the model is adequate. The ratified model equation for the study was found to be interactive, which is predominant between X1 (Inhibitor Concentration) and X3 (Time), as well as between X2 (Temperature) and X3 (Time). This indicates that the reaction time is the most significant factor (amongst the factors considered) that affected the corrosion inhibition efficiency; this was further demonstrated by the sequential increase in the response variable (weight loss, yu) with tim