Agnes Jónsdóttir (died 1507) was a prioress and later the abbess of the Benedictine convent Reynistathir abbey in Iceland from 1461 until her death in 1507.
[1] Agnes Jónsdóttir was the daughter of Búland county magistrate Jón Jónsson within the municipality of Húnaþing.
Her brothers were Ásgrimur Jónsson, the abbot of Þingeyrar cloister, and Þorvaldur at Móberg who was the father of Björg, the second wife of the lawyer Jón Sigmundsson.
The convent's overseer later became Jón Þorvaldsson, Agnes’ nephew, who eventually served as the abbot at Þingeyrar.
Agnes died at an advanced age in 1507 and Solveig Rafnsdóttir succeeded her as the last abbess of Reynistathir.