1970 Washington Senators season

The 1970 Washington Senators season involved the Senators finishing sixth in the American League East with a record of 70 wins and 92 losses. This was the franchise's penultimate season in Washington, D.C.

Offseason

 * December 5, 1969: Dennis Higgins and Barry Moore were traded by the Senators to the Cleveland Indians for Horacio Piña, Ron Law and Dave Nelson.
 * December 31, 1969: John Roseboro was signed as a free agent by the Senators.
 * January 17, 1970: Bill Madlock was drafted by the Senators in the 5th round of the 1970 Major League Baseball draft (secondary phase). Player signed May 25, 1970.
 * March 21, 1970: Brant Alyea was traded by the Senators to the Minnesota Twins for Joe Grzenda and Charley Walters.
 * March 30, 1970: Pedro Ramos was signed as a free agent by the Senators.

Opening Day starters

 * Hank Allen
 * Dick Bosman
 * Ed Brinkman
 * Paul Casanova
 * Mike Epstein
 * Frank Howard
 * Ken McMullen
 * Dave Nelson
 * Del Unser

Notable transactions

 * April 27, 1970: Pedro Ramos was released by the Senators.
 * April 27, 1970: Ken McMullen was traded by the Senators to the California Angels for Aurelio Rodríguez and Rick Reichardt.
 * May 11, 1970: Hank Allen and Ron Theobald were traded by the Senators to the Milwaukee Brewers for Wayne Comer.
 * June 4, 1970: 1970 Major League Baseball draft
 * Rick Waits was drafted by the Senators in the 5th round.
 * Bruce Sutter was drafted by the Senators in the 21st round, but did not sign.
 * August 19, 1970: John Roseboro was released by the Senators.
 * September 11, 1970: Lee Maye was selected off waivers from the Senators by the Chicago White Sox.

Starters by position
''Note: Pos = Position; G = Games played; AB = At bats; H = Hits; Avg. = Batting average; HR = Home runs; RBI = Runs batted in''

Other batters
''Note: G = Games played; AB = At bats; H = Hits; Avg. = Batting average; HR = Home runs; RBI = Runs batted in''

Starting pitchers
Note: G = Games pitched; IP = Innings pitched; W = Wins; L = Losses; ERA = Earned run average; SO = Strikeouts

Other pitchers
Note: G = Games pitched; IP = Innings pitched; W = Wins; L = Losses; ERA = Earned run average; SO = Strikeouts

Relief pitchers
Note: G = Games pitched; W = Wins; L = Losses; SV = Saves; ERA = Earned run average; SO = Strikeouts

Awards and honors
All-Star Game
 * Frank Howard, A.L. Home Run Champion 1970