Wynn Resorts' board promoted company president Matt Maddox to the position of CEO, effective immediately.
"In the last couple of weeks, I have found myself the focus of an avalanche of negative publicity," Wynn said in a statement Tuesday, according to published reports.
"As I have reflected upon the environment this has created - one in which a rush to judgment takes precedence over everything else, including the facts - I have reached the conclusion I cannot continue to be effective in my current roles."
The Wall Street Journal reported in late January that several women said Wynn harassed or assaulted them and that one case led to a multi-million dollar settlement.
The Las Vegas casino mogul, who founded the company, has denied the allegations.
Since the Journal's report, the company's shares have fallen from just under $200 to $163.22 as of Tuesday's close, wiping out billions of dollars in value. Wynn Resorts shares declined slightly in after-market trading on Tuesday.