The site will eventually have maintenance facilities for the fleet of new trains, a stabling yard for 30 trains, and a driver-training simulator.
Almost 80% of the earthworks at the depot have been completed, while more than 20km of rail track is scheduled to be laid throughout the site.
The High Capacity Metro Trains Project is expected to create around 1,100 jobs in the province.
Several workers are already employed at the site to carry out construction activities and the number is expected to reach 400 next year.
Furthermore, 100 people will be employed at the site to maintain the trains.
Victoria Minister for Industry and Employment Ben Carroll said: “Our bigger, better, next-generation trains will move more people and create 1,100 jobs across the state.
“We’re creating local jobs by building more trains to get Victorians home safer and sooner.
“Our record investment in a better transport system for Victoria is creating thousands of jobs across the state.”
Times Electric Australia is set to establish a manufacturing plant in Morwell to manufacture traction and electrical auxiliary power systems for the trains, while SIGMA Air Conditioning will supply heating, ventilation, and air conditioning systems.
Ultimate (Australia) Transportation Equipment will supply passenger seats, hand and grab rails, and other interior fittings.
Mount Waverley supplier Fire Protection Technologies will provide fire detection systems to the new trains under a six-year contract.
The new trains are scheduled to enter service from mid-2019 on the Cranbourne and Pakenham lines.