Morrison, supposed to say "global momentum to tackle climate change", mistakenly said "tackle China" during his address at the 26th session of the Conference of the Parties (COP26) to the UN Framework Convention on Climate Change, reports Xinhua news agency.
Krishani Dhanji, a political producer with Australia's SBS News, shared the video footage on Twitter, saying, "A faux pas from the PM?"
Morrison, Dhanji added, appeared to say "global momentum to tackle 'China'" instead of "climate change" before correcting himself.
The post attracted lots of comments.
"Poor fellow always switched on with anti-China mode," said a Twitter user who goes by the name Prasanna Shan.
"Well spotted. A classic Freudian slip of the tongue," said another who goes by the name Leni Barid.