- Location: Harrisburg, PA
- League: Pennsylvania State League 1893-1895; Tri-State League 1904-1914; International League 1915; New York-Penn League 1924-1935; Interstate League 1940-1942, 1946-1952; Eastern League 1987-2019; Double-A Northeast 2021; Eastern League 2022-
- Affiliation: Boston Braves 1932-1935; Pittsburgh Pirates 1940-1942; Cleveland Indians 1946-1951; Philadelphia A's 1952; Pittsburgh Pirates 1987-1990; Montreal Expos 1991-2004; Washington Nationals 2005-present
- Ballpark: FNB Field 1987-present
The Harrisburg Senators, of the Eastern League and briefly in Double-A Northeast, are a Washington Nationals' farm club nicknamed Senators that was - ironically - never affiliated with either Washington Senators iteration. They play their home games at FNB Field in Harrisburg, PA.
Just as ironically, the Nats-Senators partnership is now tied for eighth longest among teams without common ownership.
Playing on the road in their 2018 opener, the Sens won the first designated runner game in U.S. professional baseball history; the tiebreaker rule, which then existed only in the minors, starts all extra innings with the last player to complete an at-bat the previous inning on second base. The rule aims to lessen the chances of extra-inning marathons and seems to be doing so successfully.
The Senators were the first EL club to win four consecutive league titles, 1996-1999 - a feat accomplished by only a handful of clubs in the 1903-2019 Affiliated Era. Theat run followed crowns in 1987 and 1993. They were affiliated with the Montreal Expos during that historic four-year run, and the parent team supplied them with a seemingly never-ending flow of top prospects.
The Senators play Copa de la Diversión Hispanic engagement campaign games as Playeros de Harrisburg (which translates incongruously, given their home city's inland location, as the Harrisburg Beachgoers - although the ballpark is indeed on an island, albeit a river one).
The present Harrisburg Senators are one of several teams over the years to share the name. They joined the Eastern League in 1987 as a Pittsburgh Pirates' farm club. They were associated with the Montréal Expos from 1991 through 2004, during a particularly successful run, and maintained their affiliation when the Expos relocated to Washington, DC in 2005.
For their entire existence, they have played their home games at FNB Field (which was called RiverSide Stadium prior to 2004, Commerce Bank Park from 2004 through 2009, and Metro Bank Park from 2010 through 2015). 
In 1952, the Senators attempted to sign Eleanor Engle as a shortstop. The 24-year-old stenographer worked out with the club on June 22nd. Minor League Baseball President George Trautman then ruled against signing female players.
|1894||56-45||2nd||Jack Huston||Lost disputed title game|
|1895||19-16||N/A||Frank Seiss||Disbanded June 14th|
|1912||75-37||1st||George Cockill||None; League Champs|
|1913||59-52||2nd (t)||George Cockill||None|
|1914||78-32||1st||George Cockill||None; League Champs|
|1915||35-50 (61-76 overall)||6th||Eddie Zimmerman||None||Newark (26-26) moved to Harrisburg July 2|
|1924||70-60||4th||Steve Yerkes (19-16) / Mickey LaLonge (6-3) / Glenn Killinger (40-34) / Nig Clarke (5-7)||None|
|1926||47-84||8th||Rankin Johnson (35-49) / Lee Dempsey (0-1) / Joe Lightner (12-34)||None|
|1927||87-51||1st||Win Clark||None; League Champs|
|1928||82-54||1st||Glenn Killinger||None; League Champs|
|1931||83-56||1st||Joe Cobb (6-8) / Eddie Onslow (77-48)||None; League Champs|
|1941||81-43||1st||Les Bell||League Champs|
|1942||69-68||3rd||Danny Taylor||Lost in 1st round|
|1946||76-64||2nd||Les Bell||League Champs|
|1947||71-69||4th||Les Bell||Lost in 1st round|
|1949||74-64||3rd||Les Bell||Lost League Finals|
|1950||77-62||3rd||Les Bell||Lost in 1st round|
|1951||55-84||6th||Les Bell (44-63) / Harold Cox (11-21)|
|1952||46-94||8th||Buck Etchison (37-67) / Woody Wheaton (9-37)|
- "Harrisburg Senators' Metro Bank Park will get new name after bank merger." Alexandersen, Christian. PennLive.com. January 15, 2016. Access date: July 4, 2017.
- ""Senators" Poor Baseball Name. "Ponies" Suggested Instead as Title for the Islanders." Harrisburg Telegraph. April 26, 1911. Page 8.
- Andrew Linker: The Class of '93: How One Baseball Team Wrecked An Entire League, CreateSpace Independent Publishing, 2018. ISBN 978-1986602617