Microwave-assisted extraction (MAE) of polyphenols from medicinal plant, Clinacanthus nutans (C.nutans) was developed. Affecting parameters on the extraction yield of polyphenols such as ethanol concentration, solvent-to-feed ratio (S/F) and energy absorbed were studied. The variations in the effect of ethanol concentration and S/F were also explained in view of energy absorption. Polyphenols yield was found to be the maximum at 50%vol of the optimum ethanol-water composition. The yield of polyphenols was initially energy absorbed-dependent, but until some extent the solvent composition was more dominant enhancing the yield. Specific energy absorbed (J/g) was introduced in this work in order to have better understanding on effect of energy absorbed towards extractability of compounds interest. In terms of modelling, Patricelli’s model gives an excellent profiling kinetics behaviour and the prediction on the polyphenols yield as well as the extraction rate which shows better agreement with the experimental data and R2 > 0.995 at all parameters studied. A comparison study has shown that microwave pre-treatment has improved the extraction rate to about 2-5 times higher than the conventional extraction in shorter time and high equilibrium of polyphenols yield.