According to the report, Harden is alleged to have grabbed the woman's wrist and then thrown her cellphone onto the roof of a nightclub in Scottsdale, Arizona.
TMZ Sports reported a friend of Harden's gave the bystander $200 for the phone before Harden provided $300 more. The woman subsequently recovered the phone and was treated at a local hospital for a wrist injury.
Police in Scottsdale are looking into the matter but don't yet consider Harden a suspect in a crime, though his name is included in the official police report.
A little over two months remain before Harden and the Rockets tip off the 2018-19 regular season. Houston hosts the New Orleans Pelicans Oct. 17.