Monday marks a year since Palestinian militants killed around 1200 Israelis and took 250 hostages in the attack that sparked Israel's incursion into Gaza, which has killed around 41,000, according to local authorities.
Vigil organisers from the Palestine Action Group said around 500 were expected at a candlelight vigil planned at Sydney Town Hall.
Interfaith prayers would take place "to offer respect and recognition to our martyrs lost during the ongoing bloodshed by 'Israel' in Palestine and Lebanon", the group said.
"Jewish, Christian, Muslim and community members of all faiths will unite in solidarity in our call for justice and sovereignty," it said in a Facebook post.
Spokeswoman Amal Nasser told AAP the aim was for the event to be peaceful, after largely uneventful protests on Sunday under a heavy police presence.
Another pro-Palestine event, said to be backed by an extremist Islamic group, is set to take place at the Lakemba Mosque in the city's southwest suburbs.
Earlier, Victorian Premier Jacinta Allan advised against an evening vigil at Melbourne's Shrine of Remembrance.
"Today is very much a day of profound grief and trauma and deep, deep sadness for Victoria's Jewish community," Ms Allan told reporters.
"They are grieving and have been grieving for a year now, for the single biggest loss of Jewish life on a single day since the Holocaust.
Jacinta Allan is urging people to "choose love and support" on a day of "profound grief". (James Ross/AAP PHOTOS)
"Today is certainly not a day to add to that grief and trauma."
Organisers of the vigil, which will be followed by an overnight wake, said October 7 marked the first day that "Israel transformed Gaza from an "open air prison" into a "graveyard for children".
The vigil was a chance for people to show their "unrelenting resistance to the Israeli occupation, oppression and genocide of the Palestinian people", organisers said.
Pro-Palestine supporters are planning a vigil followed by an overnight wake. (James Ross/AAP PHOTOS)
Those who attend have been urged to wear black and the keffiyeh, which represents the Palestinian liberation movement.
Prime Minister Anthony Albanese and Ms Allen will attend a formal commemoration in Melbourne, organised by Zionism Victoria, for the Israeli victims of October 7.
Mr Albanese has released a recorded message mourning the loss of innocent life and denouncing anti-Semitism.
"Jewish Australians have felt the cold shadows of anti-Semitism reaching into the present day and as a nation we say, never again," he said.
Israel's military campaign has now spread to Lebanon as it pursues senior figures in Hezbollah, a Lebanese militant group backed by Iran and designated a terrorist organisation by Australia.
