The company that began in 1995 as the world's biggest bookstore confirmed that it kicked off the programme, AmazonFresh, in the Seattle, Washington, enclave Mercer Island by invitation only.
"It's up and running," said spokesman Craig Berman. "People are ordering and trucks are delivering."
"When we feel we are ready to add neighbourhoods and add more customers to the invite list, and we can provide those customers with a great experience then we will do so," he said.
Nonperishable items, already sold on Amazon.com, will also be available through AmazonFresh.
"We have 12 of our own trucks that will deliver the products to customer doorsteps," Berman said. "We even bring them inside to your kitchen."
Berman said repeated requests from customers for perishable groceries prompted the pilot programme.
The online grocery business is a difficult one, given the perishability of fresh food and the grocery industry's razor-thin profit margins.