Police say he sexually assaulted the woman after she got off a Community Transit bus Thursday night.
Two people who heard the woman's cries saw the attacker run away west on 230th Street, then north on 76th Avenue West. He then he jumped into a white van with a ladder rack on top and drove off.
The man was white, 35-to-40 years old, about 5 feet 9 inches to 6 feet tall, 180 pounds and clean shaven. He was wearing an orange jacket or hoodie, a blue baseball cap and dark pants.
Anyone with information is asked to call the Edmonds Police Department Tip Line at (425) 771-0212.