More than 1,000 personnel and 15 ships from 16 navies will be participating in the two exercises, which will be conducted in the Singapore Strait and the waters off the Indonesian island of Pulau Bintan.
The Defence Ministry said this year's exercises will, for the first time, feature multilateral information sharing and the deployment of unmanned water vehicles.
More than 40 medical practitioners from 10 countries are also meeting to discuss the topics of military diving and hyperbaric medicine.
Dr Ng Eng Hen, Singapore's Second Defence Minister, said: "Going forward, the WPNS Navies should continue to be proactive in building platforms and capacity in information exchange and operational coordination to develop their readiness to respond collectively should the need arise."
Singapore's Maritime Security Task Force Director, Rear Admiral Jackson Chia, who is also one of the co-directors of the exercises, explained why readiness and collaboration was important.
He said: "We recognise that today's maritime threats are much more complex. They are transboundary, meaning that they can originate from one place and at the end of the day, affect another partner nation. With that, it also means that no single agency or no single nation can deal with the threats effectively alone."