By applying periodic DFT computations, the possible employment of BC3 nanotube (BC3NT) as a drug delivery system (DDS) for Thiotepa (TPA) anticancer medicine has been examined. Quantum mechanics computations by the B3LYP-6–31 +G(d,p) method with dispersion correction including to be used for calculation the details of electronic, geometric, and energetic features of the interactions between TPA drug and BC3NT. The appropriate orientation for the TPA interacting with BC3NT has been assessed and adsorption energies (ΔEad) have been computed. The band distance of S and B atom in complex C2 is about 1.89 Å, also the value of ΔEad of − 29.83 kcal/mol in most stable compounds. By applying frontier molecular orbital analysis, it has been assessed that during stimulation, TPA medicine performs as HOMO and delivers the charge towards the LUMO, i.e., BC3NT. In the aqueous phase, the λmax of BC3NT-AP complex is blue-shifted by 36 nm. Drug delivery to the specific cells after protonation has been studied, due to the point that cancer cells have lower pH than others. The value of computed solvation energy (ΔEsolvation) shows the solubility BC3[email protected] system in the water phase. The effects of the present investigation verified the ability of BC3NT as a drug delivery agent for TPA in the treatment of cancer.