AmazonFresh is now available to customers in 69 central and east London postcodes who are members of the retailer's Prime subscription service, for an additional £6.99 a month.
The extra charge includes unlimited delivery for orders above £40 but deliveries under the threshold will cost £3.99 each.
The arrival of AmazonFresh, which has been operating in the US for nine years, comes after the retailer signed a deal with the supermarket Morrisons, which has agreed to provide wholesale ambient, fresh and frozen products to Amazon despite already operating its own website in partnership with Ocado.
Amazon said customers could now order their full weekly grocery shop including fresh fruit and vegetables, meat, seafood and dairy products from an initial selection of more than 130,000 items.
Major brands include Morrisons, Coca-Cola, Kellogg's, Danone, Warburtons, Walkers and Yeo Valley, while more than 50 London producers such as C.Lidgate, FishWorks, Paxton & Whitfield, Konditor & Cook, Bad Brownie and Daylesford are also involved.
AmazonFresh vice president Ajay Kavan said: "The bar in grocery retailing is exceptionally high. The supermarkets and grocers are amongst the very best retailers in the world.
"We believe that the key to the long-term success of AmazonFresh is to bring together the low prices, vast selection, fast delivery options and customer experience that Amazon customers know and love."
He added: "We are launching with a comprehensive offer in a limited area and will take our time to hone and improve our service based on our learnings and feedback from our customers.
"We will be very methodical and considered in how we roll this service out further in the UK."