The 40-year-old forward and club captain has scored 307 goals in 783 appearances since making his Roma debut 24 years ago.
He will become a director at the club he has served all his career.
"There is an agreement with the club that this will be his last year," Monchi said.
"Then he will continue as a director. I want him on my side because he is Roma and can teach me what Roma is," the Spaniard added.
Roma's final game of the season at home to Genoa on 28 May will be his last.
Totti, a World Cup winner with Italy in 2006, has won one Serie A title and two Coppa Italias at Roma.
He was widely expected to quit playing last summer but signed a one-year extension to his contract.
He has made 25 appearances this season, mostly as a substitute.
Roma legend Francesco Totti is to retire from playing at the end of the season, the club's new sporting director Monchi has revealed.