Founder Tim Martin, an outspoken supporter of the UK's withdrawal from the EU, says the changes will roll out across the chain's 880 pubs from 9 July.
The move will see champagne replaced with sparkling wines from the UK such as Denbies Sparkling Whitedowns Brut, as well as Hardys Sparkling Pinot Chardonnay from Australia.
German wheat beers will be removed in favour of UK-brewed brands including Blue Moon Belgian White, Thornbridge Versa Weisse Beer and SA Brains Atlantic White.
Wetherspoon will continue to serve Swedish Kopparberg cider, which is moving its production to the UK post-Brexit.
Martin says the new products will be cheaper than the EU brands they are replacing.
He adds that a review of all Wetherspoon products will take place over the next six to 24 months, with the aim of making the business “more competitive”.
“This move helps us to broaden our horizons so that we create an improved offer for the two million customers who visit our pubs each week,” says Martin.
“The EU’s customs union is a protectionist system which is widely misunderstood. It imposes tariffs on the 93 per cent of the world that is not in the EU, keeping prices high for UK consumers.
“Tariffs are imposed on wine from Australia, New Zealand and the US, and also on coffee, oranges, rice and more than 12,000 other products.
“There will be an inevitable transfer of trade post-Brexit to countries outside the EU, which will reduce prices in shops and pubs.”
Wetherspoon intends to honour existing contracts with EU suppliers, some of which have several years to run.
Martin has long been an outspoken supporter of Brexit. He caused a stir in the run up to the referendum in 2016 by releasing 200,000 “Vote Leave” beer mats in Wetherspoon pubs nationwide.