The bodies of David James Fisk, 57, his wife Lucita Barquin Cortez, 55, and her Filipina friend were found on Thursday at the Lake Hotel in Tagaytay, a popular resort city south of the capital Manila.
Their hands and feet were tied, police said.
The Australian couple were staying at a luxury hotel in an area popular with tourists and locals. (AP PHOTO)
The couple's family said they were praying for more information about their loved ones after police launched a manhunt.
"The love we have for our father and Lucita is so dear and this situation is like living a nightmare," the family said in a statement on Friday.
"We pray for answers and the truth in this horrific matter and just pray for their safe return to Australian shores."
The couple had travelled to Asia for two weeks, beginning the holiday in Bali before heading to the Philippines to see Ms Cortez's family and friends.
The pair were planning to return to Sydney on Saturday but their trip was tragically cut short.
Tagaytay police are now trying to identify and track down the suspects.
Chief Charles Daven Capagcuan said one of the leads is CCTV footage of a masked, hooded man carrying a sling bag walking out of the victims' room a few hours before their bodies were discovered.
He said a motive for the killings is unknown and some valuables, including the victims' phones, were not taken.
Investigators are interviewing witnesses and examining security cameras at the hotel.
Australia's Department of Foreign Affairs confirmed it was providing consular assistance to the families of two Australians who died.
"We send our condolences to the families at this difficult time," a spokesperson said in a statement.
Davis Fisk and his partner travelled to the Philippines from Bali and were due to return to Sydney. (Supplied by David Fisk & Lucita Cortez Family/AAP PHOTOS)
Tagaytay Mayor Abraham Tolentino said he was shocked by the incident and apologised to the families of the victims.
"We're very sorry to our Australian friends," he said.
"We will resolve this as soon as possible."
The remains of Mr Fisk would be flown back to Sydney and the two women would be buried in the Philippines, Mr Tolentino said.
He said the government would pay for the women's funeral and burial.
Tagaytay, about 60 kilometres south of Manila, is popular among local and foreign tourists who flock there for its cool weather and to view one of the world's smallest active volcanos nestled in the middle of a lake.
with AP
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