Rhys Williams has been announced as the Labor candidate for the seat of Mandurah.
Mr Williams has been Mandurah's mayor since 2017 but will resign in December as he moves from local to state government.
If elected, he will replace David Templeman who has served as the Mandurah MP for the last 24 years.
“The December council meeting will be my final council meeting,” Mr Williams said to reporters during Tuesday's announcement.
“It is a job that requires full-time commitment and a full-time focus and I understand that to be able to prosecute my case and WA Labor’s case here in Mandurah for re-election is also a full time commitment.
“That allows for an appropriate transition and then allows me to focus on being a candidate full time.”
Premier Roger Cook said Mr Williams is the man for the job.
"Rhys Williams gets Mandurah – he knows the opportunities this city has, and will be a strong voice for his community in our WA Labor team," Mr Cook said.
"He grew up in Mandurah and went to school locally.
"He’s been the local Mayor for seven years, helping to transform Mandurah into the modern and vibrant city it has become today.
"David Templeman leaves big shoes to fill in Mandurah, and Rhys Williams will be the champion this community needs into the future."
The Liberals are yet to name their candidate for the seat of Mandurah.
It's unknown who will step into the role of interim mayor for Mandurah once Mr Williams resigns.
Caroline Knight is currently deputy mayor.
Christmas cheers returns to Mandurah
City of Mandurah launches new community safety strategy
Winners announced for the 2024 Alcoa Peel Business Excellence Awards
Mandurah: Three girls charged with aggravated armed robbery
Teen motorbike rider critically injured in Cooloongup crash
Mandurah Estuary Bridge duplication reaches new milestone
Man charged over Karnup copper theft
The Cat Empire to headline Rockingham New Year's Eve celebrations
Two seriously injured in Casuarina crash