Origin Energy is slashing 650 jobs in a bid to reduce its operating and capital costs and boost its global competitiveness.
The majority of the job cuts will be made in the company's gas division at its Brisbane office, with a focus on reducing middle management.
The oil and gas producer and energy retailer says it is introducing a "flatter structure", with the majority of its workers on the ground and involved in the operation of its assets.
This means there will be a strong presence in regional areas, Origin Energy said.
Chief executive Frank Calabria said the changes were in the best interests of Origin becoming a "globally competitive, low cost gas producer."
"The loss of jobs is never a decision taken lightly and we are putting considerable effort into completing this process as quickly as we can so we can provide certainty to our people," Mr Calabria said.
"Extensive planning and careful consideration has been given to making sure we can implement these changes in a way that maintains business performance and Origin's very high operating standards around the safety of our people, communities and the environment."
The job cuts comes after the completion of construction of the Australia Pacific LNG project in Queensland and transition to steady operations, along with the sale of Origin's oil and gas business Lattice Energy to Beach Energy.
Staff were informed of the job cuts on Tuesday morning.
Shares in Origin Energy were down 1.1 per cent at $9.325 at 1530 AEDT, in line with other energy stocks, following a drop in oil prices overnight.
