P-glycoprotein (P-gp), which was first identified in cancer cells, is an ATP-dependent efflux transporter that expels a wide variety of cytotoxic compounds out of cells. This transporter can decrease the bioavailability of therapeutic drugs by preventing their sufficient intracellular accumulation. Over expression of P-gp in cancer cells lead to multidrug resistance (MDR) phenotype that is one of the main reasons for the failure of chemotherapy. Hence, P-gp inhibition is a favorable method to reverse MDR. In this study, the lignanamides from Cannabis sativa were docked against P-gp to recognize potential binding affinities of these phytochemicals. Tariquidar and zosuquidar, two well-known P-gp inhibitors, were selected as the control ligands. It was observed that cannabisin M and cannabisin N exhibited higher binding affinities (− 10.2 kcal/mol) to drug-binding pocket of P-gp when compared with tariquidar and zosuquidar that showed binding affinities of − 10.1 and − 9.6 kcal/mol, respectively. Based on these findings, cannabisin M and cannabisin N could be good drug candidates against P-gp.