A surveillance camera in the police station lobby captured the couple as they ran up to the counter and gestured frantically as they explained their situation to the officer on duty.
Seconds later, a police sergeant ran out from behind the counter, took the child from the man, and knelt down slightly as he turned the child onto its back. He then used the heel of his hand to deliver a series of quick blows to the toddler's back, below the shoulder blades.
After five or six blows the child relaxed, and seconds later the video showed what appeared to be the dislodged object on the floor below.
By now several other officers appeared in the lobby, and the sergeant handed the child back to the couple. Another officer gave tissues to the woman, who appeared to have been crying.
The entire rescue -- from the time the couple entered the station to the time the sergeant dislodged the object -- took barely 30 seconds.
"First Aid is very important to know and you never know when you may need to use it," officials with the Western Australia Police Force posted on Facebook along with the surveillance video. "Merry Christmas!"
The heroic cop was identified as Acting Sgt. Jason Lee by Australian news network 9News.
"Our officers receive first aid training and with several years of experience," Acting Inspector Shane Crook told 9News.
"It just sort of lifts the place," Crook said of the dramatic rescue. "I think everyone would have been all smiles ... police officers like good stories."