Currently, only 29 of the 197 signatory countries have ratified the landmark treaty agreed in December 2015.
In her maiden speech to the UN General Assembly, Ms May said: "We will continue to play our part in the international effort against climate change.
"And in a demonstration of our commitment to the agreement reached in Paris, the UK will start its domestic procedures to enable ratification of the Paris agreement, and complete these before the end of the year."
The Paris Agreement committed the world to trying to limit global warming to as close to 1.5 degrees Celsius above pre-industrial levels as possible.
However, a subsequent analysis found that individual country's pledges to reduce greenhouse gas emissions could actually allow a rise of up to 3.1C.
This year has smashed previous temperature records with the first half of 2016 1.3C warmer than the pre-industrial era of the late 19th century, according to Nasa, although this figure was inflated by the el Nino effect. Every month for the last 14 in a row has broken the record average global temperature for that month.
The Prime Minister also announced that post-Brexit Britain will remain at the heart of international affairs, and pledged hundreds of millions of pounds in aid to tackle terrorism.
She said: "The United Kingdom has always been an outward-facing, global partner at the heart of international efforts to secure peace and prosperity for all our people. And that is how we will remain. For when the British people voted to leave the EU, they did not vote to turn inwards or walk away from any of our partners in the world.”