Another part of the agreement is that members of his family can not be subject to further charges.
Russo also has agreed that his son, Vince, must plead guilty on Friday to the charges against him. All of Russo's re-election campaign money must be given either to the county or to a charity.
U.S. District Judge Kate O'Malley said Russo also must waive access to the wiretaps.
Russo did say a few words before entering the courthouse. Click on the "Web Extra" video to hear.
Russo was charged with 21 counts last week in a "bill of information," the type of court filing that usually signals a pending plea deal.
Russo, 60, of Bratenahl, resigned as auditor last week. He is said to be pleading guilty to help his son, Vince Russo, who was also charged in the probe.
His arraignment comes the day after Cuyahoga County Commissioner Jimmy Dimora, Russo's political ally and friend, was charged Wednesday in a 31-count bribery indictment.
Dimora maintains his innocence and pleaded not guilty on all counts.
Prosecutors also indicted two Cuyahoga County Common Pleas judges, a labor union business manager, a contractor and three employees in the auditor's office yesterday.
Jimmy Dimora, 7 others released on bond following corruption arrests
All seven pleaded not guilty.
Expanded Cuyahoga County corruption coverage
Regarding Russo, federal officials say Russo participated in numerous bribery schemes beginning in March 1998 and continuing through May 2009, all while serving as Auditor.
Specifically, it charges that Russo solicited and accepted things of value, such as cash, home improvements and travel to Las Vegas, Nevada, in exchange for county contracts, jobs, raises, reductions in tax valuations and other official favors.
The information also charges that Russo gave Joseph Gallucci a job and cash in exchange for running a sham campaign against him.
In addition, the information charges that Russo filed false tax returns for the years 2004 through 2008 and that he obstructed justice.
His resignation letter reads:
"I humbly submit my letter of resignation as auditor with deep, heartfelt gratitude for the opportunity to have served the citizens of Cuyahoga County for the past 26 years. I apologize to anyone I have harmed for any decision I made that embarrassed or caused harm to my office."