Halldóra Eyjólfsdóttir (died 1210; Old Norse: in Norse, Old pronounced as /ˈhɑlːˌdoːrɑ ˈœyjˌoːlvsˌdoːtːez̠/; Modern Icelandic: in Icelandic pronounced as /ˈhalˌtouːra ˈeiːjˌoul(f)sˌtouhtɪr̥/) became the first abbess of Kirkjubæjar Abbey in 1189, three years after its foundation by Bishop Þorlákur Þórhallsson, and thereby the first abbess in Iceland.
Her family and origin is unknown, except for a brother (Sokki Eyjólfsson), who died in 1211. After her death in 1210, no other abbess is known of the convent until Agatha Helgadóttir in 1293.