RAM Ratings said that the expansion of Kuantan Port, Sapangar Bay Container Port and Port of Tanjung Pelepas will require almost US$1.17 billion over the next five years.
But this figure could rise if and when Port Klang at Carey Island and the Melaka Gateway projects are launched, reports the Malaysian Star.
Such developments would represent a considerable percentage of the 100 million TEU of new container-handling capacity expected from ASEAN regional port expansions over the next 20 years.
RAM Ratings analyst Davinder Kaur said expansion projects will be incrementally started while "benefiting from the strengthening local and regional economic outlook".
Mr Kaur also reported that national ports, including Westports Holdings, Northport and Pelabuhan Tanjung Pelepas, looked stable, but were "still vulnerable to the effects of the current trend towards protectionism and changes in shipping alliances".
RAM Ratings has stated that throughput growth will be in the single digits for 2017, similar to the three per cent increase in 2016.
Malaysia continues to benefit from its strategic position along the Straits of Malacca, one of the busiest shipping lanes in the world.
In 2016, Malaysia handled more than 25 per cent of the containers passing through the ASEAN nations of Malaysia, Singapore, Thailand, Indonesia and the Philippines - or three per cent of world's box traffic.
Chinese investors have also been eyeing up Malaysia's port projects. "With China pursuing its ambitions through the One Belt, One Road plan, the prominence of the Straits of Malacca vis-a-vis global trade must be closely monitored," said Mr Kaur.