Various operational variables affecting the extraction of sludge palm oil (SPO) from palm oil mill effluent (POME) by enzymatic treatment were investigated. The enzyme used in the study was cellulase from Trichoderma reseei, commercially known as Celluclast 1.5L FG (Novozymes). A software application of the Central Composite Face-centred Design (CCFD) known as Response Surface Methodology (RSM) was used to study the effects of independent variables generated by the Design Expert Software, namely incubation time, X1 (12.73-147.27 hr), enzyme concentration, X2 (0.08%-0.92%) and rotation speed, X3 (65.91-234.09 rpm) on the oil recovered from POME. In this study, a second-order polynomial regression model was used to interpret the experimental data with a coefficient of determination (R2) value of 0.852. From the RSM-generated model, the optimum conditions for extraction of oil from POME were identified to be at an enzyme concentration value of 0.25% in 81.46 hr reaction time, with a rotation speed of 111.05 rpm. Predicted oil yield was 93.56% while the experimental oil yield was 81.95% as revealed by the One Sample T-Test of confirmatory studies.