Officers responded to the 400 block of North Hayes Avenue around 1:23 a.m. The man was pronounced dead at the scene by paramedics.
He has been identified as a 40-year-old Oxnard resident. His name is being withheld pending notification of kin.
His cause of death remains unknown, but is considered suspicious.
The investigation is ongoing. Anyone with information about this case was urged to contact Detective Bob Eckman at (805) 385-7760.