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.

Origin Energy chief executive Frank Calabria. Credit:Christopher Pearce

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.