Copyright　©　2017　Editorial　Board　of　Journal　of　Donghua　University,　Shanghai,　China.　Waterborne　polyurethane　(WBPU)　with　controlled　biodegradability　and　biocompatibility　was　synthesized　by　usingpoly　(ε-caprolactone)　(PCL)　as　the　polyglycol,　isophorone　diisocyanate　(IPDI)　as　the　isocyanate,　2,2-bishydroxymethylbutyric　acid　(DMPA)　as　the　chain　extender　and　1,　4-butanediol　(BDO)　as　the　hard-segment　regulating　agent.　We　found　that　BDO　content　significantly　influenced　mechanical　properties,　degradable　performances　and　cyto-biocompatibility　of　PCL-WBPUs.　Increasing　the　BDO　content　in　PCL-WBPU　enhanced　its　tensile　strength　and　decreases　strain.　Enzymolysis　and　hydrolysis　properties　were　also　regulated　by　BDO　content,　but　with　different　mechanisms.　Cyto-biocompatibility　was　evaluated　with　ATDC5　cells.　The　results　show　that　the　biodegradability　of　PCL-WBPU　is　significantly　determined　by　BDO　content,　which　exerts　a　serious　influence　on　its　polymer　structure,　leading　to　resultant　degradable　properties.