Prosecutors found insufficient evidence to charge Tyson or photographer Tony Echeverria, spokesman Frank Mateljan said. The two men were arrested Nov. 11 after an incident in which each claimed they were struck by the other.
Echeverria said a blow by the former heavyweight champion knocked him to the ground, and he was treated for a cut to the forehead.
Tyson was traveling with his family when he was mobbed by photographers. His attorney Shawn Chapman Holley said at the time that Tyson was protecting his infant daughter after Echeverria collided with her stroller.
She said Thursday the city attorney's office made the right decision by not charging Tyson.
"The city attorney's decision today is a small victory for those who continue o be harassed, annoyed and even stalked by the paparazzi," Chapman Holley said.
Attempts to reach Echeverria for comment were unsuccessful. Tyson also won't face any probation violations in his 2007 cocaine possession case in Arizona, said Zach Dal Pra, deputy chief of the Maricopa County Adult Probation Department.
Arizona authorities said after Tyson's arrest in Los Angeles that they were watching that case to see if the former boxer should be sent to jail for violating probation.
However, Dal Pra said Thursday his office would have to show evidence of a newer crime to revoke the probation.
Tyson became the youngest heavyweight champion ever in 1986 when he won his title as a 20-year-old. His life since then has been marred by accusations of domestic violence, rape and cocaine use.
He played himself in the 2009 hit film "The Hangover."
Associated Press Writer Amanda Lee Myers in Phoenix contributed to this report.