Objective: To construct a recombinant adenovirus(rAdCDES) which is capable of both direct and indirect treatment to mammary cancer and enhancement to the antitumor effect of radiation. Methods: A method of homologous recombination in bacteria was used to construct prAdCDglyES. The recombination adenovirus was transfected to 293 cells by liposome, in which rAdCDES was packaged and generated. The growth curve and MTT methods was used to detect the growth inhibition effect of rAdCDES on MCF-7; rAdCDES was directly injected into established MA737 tumors-bearing mice for observing difference in tumor size and survival days of mice and enhancement of the antitumor effect of radiation. Results: The inhibiting rate of rAdCDES on MCF-7 cell was (83. 1?8. 1)% and had significant difference compared with control was (19.2 ? 7.8)% (P