Prime Minister Scott Morrison said the ships were returning from a counter-drug trafficking operation in the Middle East.
Three Chinese warships have docked in Sydney Harbour for a "reciprocal visit" a day before the country marks the 30th anniversary of the Tiananmen Square massacre.
The three People's Liberation Army Navy vessels docked at Garden Island on Monday morning for a four-day stopover.
Speaking to reporters in the Solomon Islands, Prime Minister Scott Morrison said the stopover had been in place for "some time", despite the visit not being publicly announced.
"It may have been a surprise to others but it certainly wasn't a surprise to the Government," Mr Morrison said.
"Australian naval vessels have visited China. This was a program of a reciprocal visit ... That is a further demonstration of the relationship that we have."
He said the ships were returning from a counter-drug trafficking operation in the Middle East.
Tuesday marks 30 years since the deadly crackdown on the 1989 pro-democracy protests in Tiananmen Square, Beijing, which saw Chinese authorities kill hundreds of protestors and onlookers.
When asked about the timing of the two events, Mr Morrison said there was no connection.
The Department of Defence confirmed the arrival of three warships, saying it was an arrangement regularly facilitated each year.
China's request was made in April with the specific dates. Approximately 730 officers have been deployed across the three vessels - frigate Xuchang, the auxiliary replenishment ship Luoma Hu and the landing platform dock Kunlun Shan.
A spokesperson from the department said the "routine port visit" had logistical goals as well broader aims to deepen ties between the two countries.
"Port visits are conducted by all navies to undertake basic logistics and resupply activities, low level maintenance and provide valuable opportunities for crew respite.
"The Australian Government is committed to maintaining a long-term constructive relationship with China, founded on shared interests and mutual respect."
The last Australian vessel to take advantage of the reciprocal arrangement was the HMAS Melbourne, which visited the Chinese port city of Qingdao in late April as part of an International Fleet Review conducted by China's military forces.