The American star was arrested in the Santa Barbara area after she had been reported as "driving erratically" when she went out of a car park.
47-year-old Locklear was tested for drink and drugs after police had taken her to the local station.
A patrol spokesman is reported to have explained that a California Highway Patrol officer had spotted Ms Locklear's car blocking a lane while it was parked on a road in Montecito.
After speaking to her the officer suspected she was under the influence of some substance.
Earlier this year, Heather Locklear had attended a clinic because she was suffering anxiety and depression, and in 2007 she became divorced from Bon Jovi guitarist Richie Sambora after being married to him for 11 years.
