Francesca Atkinson, 40, is organising the event in memory of her friend Olivia Van Boyd, who died suddenly aged 46 two years ago.
Both women worked as medical photographers at the hospital trust and had been friends for more than 10 years.
Francesca said: "We will be walking around the hospital premises which is around a mile and encourage staff and local people to get involved."
The memory bench is earmarked to sit in the Trust grounds where Dawn dedicated over 20 years as a medical photographer.
Fran has also set up a JustGiving page in the hope of raising £350 for the bench.
"The hospital is currently becoming a memory garden for people who have lost loved ones.
"It would be amazing if we could raise enough funds to buy a bench and flowers to place in the new memorial garden at Royal Preston Hospital next to Charters Restaurant."
Fran, who worked with Dawn just short of four years but cemented their friendship in their 20s, added: "Dawn was one of the most caring, sincerest people. She was always putting other people first.
"She loved being outdoors and had a love for flowers and trees and was a spiritual person at heart.”
She added: "Let's hope for sunshine, a time to reflect and mostly to remember those that are no longer here with us, yet they are always here in spirit.
For anyone wishing to join the walk will take place on Friday, May 6 at 5.30pm.
If you would like to make a donation CLICK HERE.
Lancashire Teaching Hospitals NHS Foundation Trust is one of the United Kingdom's NHS Foundation Trusts. It provides healthcare for people in the Preston area in northwest England.
The trust runs Royal Preston Hospital on the northern outskirts of the city in the Fulwood area and Chorley and South Ribble Hospital.