Ramp-up to full production is expected to take up to two weeks.
Previously, the state-owned company had said the shutdown would cost about 210 million kinas ($58.07 million) of revenue, which would directly hit foreign currency inflows as the country battles an economic slump.
However, despite the temporary suspension of operations, Ok Tedi is forecasting a solid profit outlook for the year.
The Ok Tedi mine is an open-cut copper, gold and silver mine located at Mt. Fubilan in the Western Province of Papua New Guinea.
Approximately 240 thousand tonnes of overburden (waste rock) is mined each day from a pit covering about 2.6 square kilometres. In addition, about 60 thousand tonnes of ore is mined each day and delivered to the mill for processing.