Oasis is a small unincorporated community located in Johnson County, Iowa, United States. It lies within section 26 of Graham Township, and was once known as Graham, Iowa. It is part of the Iowa City, Iowa Metropolitan Statistical Area. As of 2005, the town had a total population of approximately 20. It contains several homes, a cemetery, and a functioning grain elevator. It was once a stop on The C RI & P Railroad, whose bed has now become the Hoover Nature Trail which runs from Oasis to West Branch. West of town is the Oasis Cemetery.