Purpose:　The　objective　of　this　research　was　to　reveal　the　thermal　characteristics　of　microwave　ablations　in　the　vicinity　of　an　arterial　bifurcation.　Methods:　The　temperature　distribution　after　microwave　heating　of　a　liver-like　material　in　the　close　proximity　of　an　arterial　bifurcation　was　simulated　using　the　finite　element　method.　Coupled　fluid　flow　and　solid　heat　transfer　were　taken　into　consideration　and　a　three-dimensional　analysis　was　performed.　An　experimentally　determined　SAR　(specific　absorption　rate)　generated　by　the　absorption　of　microwaves　in　liver-like　material　was　used　in　the　analysis　instead　of　utilizing　electromagnetic　calculations.　Several　different　tests　of　time-controlled　ablations　with　varying　distances　between　the　microwave　antenna　and　the　bifurcation　were　performed　and　detailed　temperature　distributions　near　the　bifurcation　were　obtained.　Results:　The　interaction　between　the　recirculation　flow　in　the　bifurcation　and　the　heat　transfer　in　the　surrounding　tissue　makes　the　temperature　distribution　near　the　bifurcation　complicated.　Most　importantly,　after　a　period　of　continuous　heating　with　constant　microwave　output　power,　the　maximum　temperatures　caused　by　the　ablation　did　not　always　increase　with　the　distance　between　the　antenna　and　the　bifurcation.　Conclusion:　It　can　be　concluded　that　inadequate　ablations　can　be　the　result　not　only　from　a　close　proximity　between　the　antenna　and　the　blood　vessel,　but　also　from　a　complicated　blood　flow　in　large　vessels　whose　structure　causes　recirculation　flow.