The South American nation has seen 12 days of massive protests to demand greater economic equality and better public services in a country long seen as an economic success story.
Patricia Espinosa, executive secretary of the UN Framework Convention on Climate Change (UNFCCC) based in Bonn, Germany, said in a statement that she was informed of the "decision by the government of Chile not to host COP25 in view of the hard situation that the country is undergoing".
"A president must always put his compatriots above all else", he said.
The upcoming APEC summit was seen as a key opportunity for leaders from advanced and emerging economies to engage in bilateral talks on the fringes of the multilateral parley.
White House officials said President Donald Trump had been planning to meet Chinese President Xi Jinping there to discuss a possible trade deal. The two leaders were set to sign an interim trade deal next month at the summit.
The metro public transport system in the capital suffered almost $US400 million in damages.
Clashes between protesters and security forces, which were sparked by a hike in metro fares in the country's capital, have spread nationwide, leaving at least 18 people dead and leading the government to declare a state of emergency and impose curfews.
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Pinera cited ongoing violent protests that have plagued the country for weeks as the reason for the APEC and COP25 summit cancellations. "I imagine the meeting is scheduled for Chile", he said.
Chile agreed to organise the annual climate summit - scheduled to take place from December 2-13 - after previous host Brazil a year ago withdrew its offer under newly-elected far-right President Jair Bolsonaro.
It came just days before Trump is expected to formalize his government's withdrawal from the Paris Agreement on November 4.
The decision is a major blow to Chile's image as a regional oasis of stability and economic development.
With Pinera's popularity at an all-time low, Chileans were calling for new protests and the United Nations was sending a team to investigate allegations of human rights abuses.
Costa Rica hosted a smaller climate change meeting, known as PreCOP25, earlier this month.