The Singapore Refining Company plans to pump more than US$500 million (S$633 million) into installing new facilities at its refinery on Jurong Island, it said on Tuesday.
It wants to add a gasoline clean fuels facility and a cogeneration plant.
The gasoline clean fuels facility will let it produce transportation fuels to meet increasingly stringent gasoline quality specifications in the region, it said in a statement.
It added that the cogeneration plant will let it generate its own electricity supply and boost energy efficiency, which would help to lower greenhouse gas and sulphur oxide emissions.
The company is the smallest of the three oil refining companies here, after Exxon Mobil and Shell.
It processes up to 290,000 barrels of crude oil per day producing liquefied petroleum gas, gasoline, jet fuel, diesel, fuel oil and asphalt.
It is half-owned by United States oil major Chevron and the Singapore Petroleum Company, which is a unit of Chinese oil firm PetroChina International.
The firm's chief executive Mr James Er said in a statement that installing the new facilities was a "significant investment" in the company by its shareholders and represented "a major commitment to the future competitiveness of the refinery".
He said the building of the new facilities would also create jobs for around 2,000 engineers and construction workers on site during the construction.