Whalen is a surname.
In Ireland, Whalen, Whelan, Phelan and O'Phelan, are anglicized variants of the same Gaelic surname, Faoláin, which itself is a variant of Ó Faoileáin and Ó Haoláin.
It may refer to: In Britain, Whalen is an old English-language spelling for the village Uelen.