Ryan has been reported involved in a power struggle within the Texas organization and there had been speculation early in the season that he was on the verge of leaving the team, but he remained on the job throughout the season.
During a news conference Thursday, Ryan said he had maintained a strong bond with the clubs owners as well as General Manager Jon Daniels.
"I feel my relationship with Jon is good and our relationship didn't come into play on this," Ryan said.
Ray Davis and Bob Simpson, co-owners of the team, attended the news conference.
Ryan's position will not be filled when he officially steps down Oct. 30.
Davis said he and Simpson would jointly handle the team's dealings with Major League Baseball.
"This closes a chapter of my life in baseball," Ryan said. "I feel like it is time for me to move on and do other things. This is a decision that has been weighing on me, but I feel like it's the right decision."
The Rangers' only two appearances in the World Series have come during Ryan's tenure, which began in 2008.
Ryan said he did not plan on working for the Houston Astros, which had become a matter of speculation when his son was hired this year as that team's president of business operations.
"That's not in my plans," Ryan said. "I plan on going home, back to my ranch (in south Texas) and spending some time with my grandkids and family."
Ryan threw seven no-hitters during his career, which began in 1966 when Ryan was 19. He pitched for the New York Mets, California Angels, Astros and Rangers. He spent the final four years of his career with Texas and retired as a player after the 1993 season.
He recorded a major league record 5,714 strikeouts during 807 regular season games.
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