More than 380 people are now dead, hundreds have been injured and many homes, businesses and local services have been destroyed after an earthquake triggered the giant wave.
Scottish Catholic International Aid Fund (SCIAF) is in contact with its sister agency, Caritas Indonesia, who are responding on the ground.
SCIAF’s director Alistair Dutton said: “I’m deeply concerned to see the news of deaths, injuries and destruction following the terrible tsunami which has hit Palu city in Indonesia.
“My thoughts and prayers are with those who have lost loved ones and are now left to pick up the pieces and rebuild their lives.
“We in SCIAF have already released £20,000 and are contacting our partner, Caritas Indonesia, to determine what more we can do to help.”
Three-metre-high waves swept through the city of Palu on Sulawesi island following a magnitude 7.5 earthquake just off the coast on Friday evening.
Strong aftershocks have continued to hit the city on Saturday.
The injured are being treated in the open air and residents are advised not to return to their homes.
There is an urgent need for temporary shelters, food and clean water.
Thousands of homes have been destroyed together with hospitals and hotels.
The main road in Palu is currently blocked after a landslide, and the airport is closed due to damage to the runway.