The global energy, commodities and financial markets specialist said it had received regulatory approval from the Australian Securities and Investment Commission.
Marex Solutions head of APAC sales Nick Burke will run Marex Australia, which will provide local clients with over-the-counter derivative products to hedge commodity and foreign exchange price risk.
This product set will then be expanded to include futures execution, clearing services and broader OTC offerings.
"This is an exciting development for Marex as we grow our presence and increase our headcount in the region," Burke said.
"There are tangible opportunities, including providing Australian-based clients with improved market access to exchange traded derivatives and clearing via our proprietary technology platforms.
"We look forward to offering our suite of innovative cross-asset OTC products to clients locally."
Marex has 1100 global employees, including about 70 in Hong Kong and Singapore.
"Developing Asia Pacific is a central part of our stated global growth strategy, with a key strand being the launch and expansion of an Australian branch," Marex CEO Ian Lowitt said.
"As one of the largest markets for agriculture, energy and metals, Australia is a hugely important geography for our business and where it is essential to have a physical presence. We look forward to offering our comprehensive risk management solutions to the Australian agricultural, commodity and financial sector."