Given the increase in global mortality rate due to various types of cancer, the present study aimed to develop optimal conditions for the synthesis of cellulose-magnesium oxide nanocomposite with favorable anticancer activity. For this purpose, the Taguchi method was used to design nine experiments with varied ratios of cellulose biopolymer, magnesium oxide nanoparticles and different stirring times. The scanning electron microscopy (SEM) images confirmed the formation of cellulose-magnesium oxide nanocomposite. The anticancer activity level of nine nanocomposites studied was evaluated using MTT assay on Michigan Cancer Foundation-7 (MCF-7) cell line. The nanocomposite synthesized in experiment 9 (8 mg/ml of magnesium oxide, 2 mg/ml of cellulose and stirring time of 60 min) showed the highest growth inhibitory activity on the cancer cells. Based on the attained results,e cellulose-magnesium oxide nanocomposite synthesized in optimal conditions can be used as an eligible anticancer agent.