He said after Tuesday's game against Tampa Bay that his throwing arm was worn down and that further surgery would not be an option.
He made a surprise visit to Tuesday's game at Topicana Field to discuss his immediate future with Cincinnati general manager Jim Bowden.
Rijo, 38, underwent his sixth elbow surgery in March. He had been participating in extended spring training, and recently took a 10-day break from throwing. The right-hander reported that he tried throwing earlier Tuesday at the Reds' training complex in Sarasota, Fla.
He didn't like the results.
"It doesn't feel too good," Rijo told MLB.com, the official Web site of Major League Baseball. "It feels worse now than it did before."
Rijo has a 116-91 career record, and was named MVP in the 1990 World Series.