Board Thread:Theories and Speculation/@comment-28550406-20160601140633/@comment-26773508-20160601152937

We don't know. She is of Senju/Uzumaki heritage. That doesn't necessarily mean her surname/family name/clan name will be Senju/Uzumaki. If Tsunade's mom was Hashirama's own daughter who married to a different clan, then her surname would be different. But she still has a strong Senju/Uzumaki heritage.