Reese Witherspoon -- Big Black Eye After Car Accident

Reese Witherspoon is still bearing the scars from a run-in with a car last week -- sporting a big black eye ... 6 days after she was run over by an 84-year-old woman.

Reese was out in L.A. yesterday, smiling on her way to a birthday party -- despite the big band-aid on her forehead.

A different photo that we quickly learned had been taken BEFORE the accident had made the rounds last week showing Reese looking fine ... but the fact is, that photo was taken before Reese was hit by a car in Santa Monica.

As TMZ previously reported, Reese was hospitalized after the accident on Wednesday, but she was soon released after doctors determined her injuries were only minor.