The Australian Maritime Safety Authority (AMSA) said in a statement that it had plotted the position of the object in the Chinese photos and it had fallen within Saturdays search area although it was not sighted then.
Experts believe the shape and size of the object measuring 22 meters by 13 meters could be consistent with a wing from a Boeing 777 airliner.
The Chinese satellite photos were taken two days after Australian satellite photos that showed another object measuring 24 meters long in waters more than 1,400 km southwest of the Australian city of Perth.
The locations of the photos were about 120 km apart.
The AMSA statement said a civil aircraft tasked by AMSA reported Saturday sighting a number of small objects with the naked eye, including a wooden pallet, within a radius of 5 km.
A Royal New Zealand Air Force (RNZAF) P3 Orion aircraft with specialist electro-optic observation equipment was diverted to the location, arriving after the first aircraft left, but only reported sighting clumps of seaweed.
The RNZAF Orion dropped a datum marker buoy to track the movement of the material and a merchant ship in the area has been tasked to relocate and seek to identify the material.
Weather conditions in the search area were on Saturday with visibility of around 10 km and moderate seas.
The Royal Australian Air Force, the Royal New Zealand Air Force, two chartered civil aircraft and two merchant ships supported Saturdays search effort in a 36,000 square kilometre search area in the Australian Search and Rescue Region.
Four military aircraft assisted in Sundays search, as well as two ultra-long range jets.
The Royal Australian Navys HMAS Success has arrived in the search area. Two merchant ships are also in the search area.