Police are appealing for witnesses to a crash which claimed the life of a 29-year-old woman at Lake Munmorah.

Police believe a Subaru WRX collided with a Toyota Landcruiser on the Pacific Highway near Colongra Bay Road around 8.15pm on Friday, causing the Landcruiser to hit a power pole.

The woman was driving the Toyota and died at the scene.

Her passenger, a 5-month-old girl was freed by passers-by and taken to the John Hunter Hospital for observation.

A 34-year-old man driving the Subaru was also taken to the John  Hunter under police guard for mandatory testing and observation.

His 28-year-old male passenger suffered minor injuries.