The $66.7 million deal was signed on Sunday between the two firms.
The 183-metre long tankers will each have a deadweight of 46,200 metric tonnes and a capacity for 54,300 cubic metres of liquid petrochemicals, NCC said in a statement.
Under the deal, Hyundai Mipo is scheduled to complete the construction of the tankers in 2005.
NCC already has 12 tankers for transporting petrochemicals with a total capacity of 350,000 tonnes.
Like most of the tankers, the two new carriers will be chartered to petrochemicals giant, Saudi Basic Industries Corportation, SABIC, on long-term contracts.
Saudi Arabia is a leading petrochemicals producer with several million tonnes of output every year, mostly for export.