Labor upper house MP Pierre Yang appealed to the Returned & Services League WA to include the group after being approached by some of the relatives who live in his electorate and knew he had served in the Australian Army Reserves.

Descendents of Chinese veterans marched in Melbourne for the first time in 2016 and in Sydney in 2015.

It's now Perth's turn to demonstrate recognition of their fight alongside the Allies against a common enemy.

"The Japanese Imperial Army was unstoppable," Mr Yang told AAP.

"It was a formidable opponent.

"I'm very heart-warmed and appreciative of the RSL for looking at it and making a decision based on the facts."

About 19 descendants are expected to march on Wednesday.

RSL WA chief executive John McCourt said the branch strongly welcomed their participation.

"Another group that will have many people marching for the first time behind their own banner are servicemen and women who have served in the Australian Defence Force anytime since 1990," Mr McCourt said.

"This will allow anyone who has served in the ADF, regardless if their service, who have been overseas on operational deployments or here in Australia.

"They can also be a former or current serving ADF member; either a Reservist or permanent member."

About 180 groups will take part in total including bands.

RSL WA-hosted commemorative events within the city are expected to attract more than 100,000 people.

This year holds special significance as it is the 100th anniversary of the end of WWI.

Australian Associated Press