The fire broke out just before 2 p.m. in the 9200 block of Delridge Ave. SW, Seattle Fire officials said.
Fire officials initially said on Twitter that everyone reportedly made it out safely. But when crews knocked out the blaze, they found a man dead in the back bedroom of the house. It's not clear yet how the man died but officials say that's where the fire began.
Four puppies also died in the fire. However, firefighters did rescue two dogs and another puppy.
Updates to follow as more details become available