The baby was spotted sleeping in the vehicle near the Mermaid Strip Club in Wellington, New Zealand, at 3am yesterday morning.
Police arrested the 42-year-old father and took the baby to hospital.
He is facing a charge of leaving a child under 14 without reasonable supervision, Inspector Simon Perry said.
A child welfare agency has been awarded custody of the tot for five days while its future is decided.
New Zealand's commissioner for children, John Angus, called it an "extreme form of neglect".
He said: "I would commend the member of the public who saw this poor child in the car and took some action to make it safe."
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