Aim:　A　hypoxia-activated　combi-nitrosourea　prodrug,　N-(2-chloroethyl)-N＇-2-(2-(4-nitrobenzylcarbamate)-O-6-benzyl-9-guanine)ethyl-N-nitrosourea　(NBGNU),　was　synthesized　and　evaluated　for　its　hypoxic　selectivity　and　anticancer　activity　in　vitro.　Results:　The　prodrug　was　designed　as　a　tripartite　molecule　consisting　of　a　chloroethylnitrosourea　pharmacophore　to　induce　DNA　interstrand　crosslinks　(ICLs)　and　an　O-6-benzylguanine　analog　moiety　masked　by　a　4-nitrobenzylcarbamate　group　to　induce　hypoxia-activated　inhibition　of　O-6-alkylguanine-DNA　alkyltransferase.　NBGNU　was　tested　for　hypoxic　selectivity,　cytotoxicity　and　DNA　ICLs　ability.　The　reduction　product　amounts,　cell　death　rates　and　DNA　ICL　levels　induced　by　NBGNU　under　hypoxic　conditions　were　all　significantly　higher　than　those　induced　by　NBGNU　under　normoxic　conditions.　Conclusion:　The　tripartite　combi-nitrosourea　prodrug　exhibits　desirable　tumor-hypoxia　targeting　ability　and　abolished　chemoresistance　compared　with　the　conventional　chloroethylnitrosoureas.