Frans Gustaf Abraham Dahl (13 February 1835 – 21 September 1927) was a Swedish architect.

[1] He is known for designing several of Sweden's prominent buildings, including Stockholm's National Library of Sweden and Mariahissen.

He also designed Norrby Church in Sala Municipality.

Dahl had two known children: fellow architect Theodor Dahl (father of author Tora Dahl) and Elsa Åkerhielm.

He was a cousin of composer Viking Dahl.