Davao del Sur's 1st congressional district

Davao del Sur's 1st congressional district is an obsolete congressional district in Davao del Sur for the House of Representatives of the Philippines from 1987 to 2016. The district encompassed seven northern local government units of the previously undivided province bordering Davao City and includes Digos, the provincial capital. It was created ahead of the 1987 Philippine House of Representatives elections following the ratification of the 1987 constitution which established two districts for the province and another three districts for Davao City. Prior to the 1987 apportionment, Davao del Sur residents elected their representatives to the national legislatures on a provincewide basis through the Davao del Sur's at-large congressional district. The district was last contested at the 2013 Philippine House of Representatives elections. Davao del Sur returned to electing its representatives at-large in 2016 after losing most of its southern territory to the province of Davao Occidental created by Republic Act No. 10360 on January 4, 2013.

Representation history
{| class=wikitable ! rowspan="2" | # ! rowspan="2" colspan=2 | Member ! colspan=2 | Term of office ! rowspan="2" | Congress ! rowspan="2" | Party ! rowspan="2" | Electoral history ! rowspan="2" | Constituent LGUs !Start!!End
 * colspan="9" style="text-align:center;" |
 * colspan="9" style="text-align:center;" |

Davao del Sur's 1st district for the House of Representatives of the Philippines

 * colspan="9" style="text-align:center;" | District created February 2, 1987 from Davao del Sur's at-large district.
 * style="text-align:center;" | 1
 * style="color:inherit;background:;" |
 * Juanito G. Camasura Jr.
 * June 30, 1987
 * June 30, 1992
 * style="text-align:center;" | 8th
 * PDP–Laban
 * Elected in 1987.
 * rowspan="9" style="text-align:center;" | 1987–2016 Bansalan, Digos, Hagonoy, Magsaysay, Matanao, Padada, Santa Cruz
 * style="text-align:center;" | 2
 * style="color:inherit;background:;" |
 * Alejandro Almendras
 * June 30, 1992
 * June 30, 1995
 * style="text-align:center;" | 9th
 * Lakas–CMD
 * Elected in 1992.
 * style="text-align:center;" | 3
 * style="color:inherit;background:;" |
 * Alejandro Almendras Jr.
 * June 30, 1995
 * June 30, 1998
 * style="text-align:center;" | 10th
 * Lakas–CMD
 * Elected in 1995.
 * rowspan="3" style="text-align:center;" | 4
 * style="color:inherit;background:;" |
 * rowspan="3" | Douglas Cagas
 * rowspan="3" | June 30, 1998
 * rowspan="3" | June 30, 2007
 * style="text-align:center;" | 11th
 * LAMMP
 * Elected in 1998.
 * rowspan="2" style="color:inherit;background:;" |
 * style="text-align:center;" | 12th
 * rowspan="2" | NPC
 * Re-elected in 2001.
 * style="text-align:center;" | 13th
 * Re-elected in 2004.
 * rowspan="2" style="text-align:center;" | 5
 * rowspan="2" style="color:inherit;background:;" |
 * rowspan="2" | Marc Douglas Cagas IV
 * rowspan="2" | June 30, 2007
 * rowspan="2" | June 30, 2013
 * style="text-align:center;" | 14th
 * rowspan="2" | Nacionalista
 * Elected in 2007.
 * style="text-align:center;" | 15th
 * Re-elected in 2010.
 * style="text-align:center;" | 6
 * style="color:inherit;background:;" |
 * Mercedes C. Cagas
 * June 30, 2013
 * June 30, 2016
 * style="text-align:center;" | 16th
 * Nacionalista
 * Elected in 2013. Redistricted to Davao del Sur's at-large district.
 * colspan="9" style="text-align:center;" | District dissolved into Davao del Sur's at-large district.
 * }
 * style="text-align:center;" | 6
 * style="color:inherit;background:;" |
 * Mercedes C. Cagas
 * June 30, 2013
 * June 30, 2016
 * style="text-align:center;" | 16th
 * Nacionalista
 * Elected in 2013. Redistricted to Davao del Sur's at-large district.
 * colspan="9" style="text-align:center;" | District dissolved into Davao del Sur's at-large district.
 * }
 * }