Byrne, 54, called himself a "conservative reformer" as he announced he would seek the governor's office in the 2010 elections.
The announcement in Spanish Fort was the first of four planned by Byrne, a Baldwin County attorney and former state senator who also has served on the state school board. He was joined by his wife, Rebecca, and their four children as about 100 supporters cheered the announcement.
Other campaign stops Wednesday were scheduled in Montgomery, Birmingham and Huntsville.
Byrne promised he would make ethics, education improvements and economic development his priorities as governor.
"The biggest issue is ethics reform," Byrne said, pointing to scandals in the two-year college system. Along with a former chancellor and several two-year college officials and employees, two legislators have been convicted and one pleaded guilty in a probe of financial corruption in the system.
Byrne said he also favors an end to the mingling of campaign contributions between political action committees and would call a special session in 2011 to put pressure on legislators to pass tougher ethics laws.
"Make it 'the' issue in the campaign for everybody," Byrne said.
Byrne praised Republican Gov. Bob Riley, who named him chancellor to clean up corruption in the two-year colleges in 2007, but said he expects Riley to remain neutral in the GOP primary.
"I don't anticipate he'll be endorsing in the race," Byrne said.
State Rep. Robert Bentley of Tuscaloosa and Greenville businessman Tim James are the only other announced GOP candidates for governor.
Byrne said he doesn't know how much he will need to finance his race.
"I don't have the personal wealth to put my money into the campaign. I'll have to raise it," he said.