A series of novel benzyloxyurea derivatives was designed, synthesized by substituting different benzyls or phenyls on N,N'-positions of the hydroxyurea (HU). These target compounds were evaluated for their anticancer activity in vitro against human leukemia cell line K562 and murine leukemia cell line L1210 in comparison with HU by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Some of the compounds showed promising anticancer activity against the cells. Molecular docking experiments with Saccharomyces cerevisiae R1 domain indicated that 4a and 4f' have stronger affinity than 4m and 4n. Flow cytometry study showed that compound 4g exerted greater apoptotic activity against K562 cells line than HU.