"We sadly announce the tragic loss of two workers and 16 injured from a fire incident near Alwesa," the Saudi company said on its Twitter account.
Yesterday Saudi Aramco said only that several workers were injured, and operations were unaffected.
It has not given the cause of the blaze.
The company is at the heart of Saudi Arabia's wide-ranging Vision 2030 plan to wean the economy of the world's biggest petroleum exporter off oil.
The proceeds would help form what will become the world's biggest state investment fund, with around USD 2 trillion in assets.