Walmart said its decision came after the company reviewed its firearm sales policy in light of the mass shooting at Marjory Stoneman Douglas High School in Parkland, Florida, that killed 17 people. The teenage gunman used an AR-15 rifle. It said it takes "seriously our obligation to be a responsible seller of firearms" and also emphasized its background of serving "serving sportsmen and hunters."
The retail giant said it will update its processes "as quickly as possible to implement this change."
Walmart stopped selling "modern sporting rifles," including the AR-15 in 2015.
It doesn't sell bump stocks, the accessory attached to a semi-automatic gun that makes it easier to fire rounds faster. It also doesn't sell large-capacity magazines.
The company also said it is removing items from its website that resemble "assault-style rifles," including nonlethal airsoft guns and toys.
It also says it doesn't sell handguns, except in Alaska.
Walmart's announcement came the same day as Dick's Sporting Good's announced that it would stop selling "assault-type" rifles.
The Associated Press contributed to this report.