The cockpit voice recorder - part of two recorders that make up the black box - was also located 20 metres from the flight data recorder but has not been retrieved yet.
"I received information from the National Transport Safety Committee chief that at 07:11 am (local time), we have managed to get part of black box or the flight data recorder (FDR)," Fransiskus Bambang Soelistyo, chief of Indonesia's search and rescue agency Basarnas, told reporters.
The flight data recorder was found under the debris of the Airbus A320-200's wing.
Investigators will now examine the recorder for any leads in to determine the cause of the crash that claimed all 162 lives on board the ill-fated AirAsia Flight QZ8501, en route from Indonesia's Surabaya city to Singapore on December 28.
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Meanwhile, the cockpit voice recorder "seems to be under a wing, which is quite heavy," said S B Supriyadi, search and rescue agency coordinator.
The official gave new dramatic details of the accident, saying an initial analysis of the wreckage recovered so far indicated the plane exploded on impact with the water due to a rapid change in pressure.
"It exploded because of the pressure.
"The cabin was pressurised and before the pressure of the cabin could be adjusted, it went down -- boom. That explosion was heard in the area," he said, adding the left side of the plane seemed to have disintegrated.
However, some media reports said there was no data "to support the explosion theory", citing an official.
Only 48 bodies, including at least two strapped to their seats, have been found in the choppy waters so far despite over two weeks of search operations.
Officials have said the multi-national search operation's top priority will be recovering bodies, and then retrieving the black box.