The move is in response to seasonal demand but also follows United Airlines' upgrading of its Melbourne-LAX route to a direct service on a Boeing 787-9 from late October.
Qantas International CEO Simon Hickey says the airline will add "up to 11 trans-Pacific flights over the Christmas holidays, primarily from Melbourne to Los Angeles", according to The Sydney Morning Herald.
"That is part of being nimble and making sure we have got the right network for when we need it," Hickey said.
Qantas currently runs a single daily flight between Melbourne and Los Angeles on its flagship Airbus A380, but could roster a Boeing 747 as the second service over the December-January period.
The airline will also bring the A380 back onto its Sydney-Hong Kong route from 11 December 2014 to 26 January 2015 as a demand-driven seasonal measure, having withdrawn the superjumbo in favour of a Boeing 747 as of September 29 this year.