The province is currently represented in the lower house of the Congress of the Philippines through its first and second congressional districts.
[1] Agusan del Sur was represented in the Interim Batasang Pambansa as part of Region X from 1978 to 1984, and returned one representative, elected at large, to the Regular Batasang Pambansa in 1984.
Between 1916 and 1935, the territory of what is now Agusan del Sur (then part of the undivided province of Agusan) was represented in the Senate of the Philippines through the 12th senatorial district of the Philippine Islands.
However, in 1935, all senatorial districts were abolished when a unicameral National Assembly was installed under a new constitution following the passage of the Tydings–McDuffie Act, which established the Commonwealth of the Philippines.
Agusan del Sur has been represented in the lower house of various Philippine national legislatures since 1987 through its first and second congressional districts.