A killing and related injuries last month in Port Vila prompted the call for action.
Chief Isaac Warwor said he expects around 500 people from Vanuatu's Christian Council, other chiefs groups, women's organisations and the National youth council at the march.
He said Vanuatu kastom and the law both need strengthening to help defeat violence.
"If somebody's dead it's simple, the law has to come in to penalise who did the action, but the kastom has to also come in to make sure we always have peace," he said.
