The footage, released Monday, begins with a father begging for help and running toward the sergeant last week as he holds his unconscious child.
"Please officer! Please! I don't know what's wrong!" the man cries out.
The father watches helplessly as the sergeant calls dispatch to get an ambulance to the scene for the baby girl.
As the sergeant works to clear the girl's airway, the worried mother arrives and yells out "Please! What's going on?!"
The sergeant begins patting the child on her back to help clear her airway. To the relief of everyone, the girl began to breathe.
CHP officer saves choking 6-month-old baby along 101 Freeway
CHP officer saves 6-month-old choking baby along 101 Freeway
According to the Los Angeles Police Department, the sergeant found a "choking hazard inside the child's airway," and he performed a finger sweep and back thrust to help her breathe again.
"As a result of his efforts, the unknown choking hazard dislodged and the child regained consciousness," police said.
The baby was taken to a hospital and is in stable condition, according to a news release.
The name of the sergeant has not been made public.