Collaborators will trial their service in Florida, although timing has yet to be confirmed
Ford, Walmart and Postmates will work together to develop and trial a delivery service using autonomous vehicles.
The companies have revealed the trials will take place in Miami-Dade county in Florida, but haven't announced when it will begin operation.
Ford has previously stated it wants its autonomous delivery vehicles to start commercial service around 2021. It expects to invest around US$4 billion ($5.6 billion) in autonomous development over the next five years.
The company says it will study Walmart's operational processes over the next few months, and work with the retailer to determine which goods are suitable for autonomous delivery.
They will also explore vehicle choice, and develop any necessary modifications to help prolong the life of perishable goods and account for vehicles making multiple deliveries during the one trip.
With no on-board driver, the car and storage area will need to be modified to allow customers to collect their goods without any human interaction.
The other partner in this collaboration is Postmates, an on-demand service for delivering food, drinks and groceries. Postmates is expected to provide much of the backend computing infrastructure for the trial and any future commercial service.
Although Amazon dominates the online retail sector, and has made headlines in the past for its planned drone delivery scheme, Walmart is still America's top retailer with over 5000 stores in the US, selling everything from fresh fruits and vegetables to flat-screen televisions.