A New Zealand woman has been arrested on a child neglect charge after a bus driver found a two-year-old girl alive in a suitcase that was stowed in the luggage compartment.

The bus driver noticed movement inside the bag during a planned stop on Sunday at the settlement of Kaiwaka, north of Auckland, after a passenger asked for access to the luggage compartment, Detective Inspector Simon Harrison said.

When the driver opened the suitcase, the two-year-old girl was found, very hot but otherwise appeared physically unharmed, Harrison said.

The child was taken to a hospital, where she remained on Sunday night.

The arrested woman was charged with ill-treatment or neglect of a child and will appear in court on Monday.