The bank's customers will be able to pay with just a swipe of their debit card from June with Barclays' Contactless Mobile app, which will be integrated with its own existing banking app.
The bank is trumpeting the ease of having account details already set up and the ability to view mobile transactions through the app, which is used by five million of its customers.
"It’s all there, in one place, ready to go with no need to enter card details, delivering a brilliant experience in an instant," said Barclays UK chief executive Ashok Vaswani.
Android Pay is due to launch imminently in the UK, supported by several big banks, including HSBC and Lloyds. But, Barclays is taking advantage of Android being open source, pursuing its own app strategy.
It's a different approach than it took with Apple, which does not give open access to the NFC technology needed for mobile pay. Apple Pay launched last year, with Barclays eventually jumping on board in April.
Barclays is understood to be the first British bank to offer its own contactless pay app.
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“A service built around Barclays' customer base is smart, and support for NFC-led services means hundreds of thousands of locations in the country will support it. The contactless limit being higher than Android Pay is another bonus," said Ernest Doku, telecoms expert at uSwitch.
“But most customers want one mobile payment app, not different apps for multiple services - this will make for a fractured experience," he added.
Payments can be made up to £30 with a simple swipe, but payments of up tp £100 can be made by entering the card's pin through the app.
The bank has also focused on its own payment methods with a range of wearables, including a wristband, key fob and sticker that attaches to your phone, called bPay.