[en] Density functional calculations at the B3LYP level were performed to understanding into the structure of the third generation anticancer drug, oxaliplatin. The structure and frequency spectrum were calculated, and oxaliplatin monohydrates were studied. The calculated structure parameters were agreed with the experimental data. While there were some differences in frequency spectrum between the calculated data and the experimental data. The calculation also give out the most probably structure of oxaliplatin monohydrate. (author)