The company said in a statement Thursday that it decided to review its firearm sales policy "[i]n light of recent events."
"Going forward, we are raising the age restriction for purchase of firearms and ammunition to 21 years of age. We will update our processes as quickly as possible to implement this change," a statement said.
"We are also removing items from our website resembling assault-style rifles, including nonlethal airsoft guns and toys," the company said. "Our heritage as a company has always been in serving sportsmen and hunters, and we will continue to do so in a responsible way."
The news comes amid a broad public push to tighten gun regulations in the wake of a mass shooting at a Florida high school on February 14 that left 17 people dead.
Dick's Sporting Goods, the nation's largest sporting goods retailer, said on Wednesday it would stop selling assault-style weapons like the one used in the Parkland, Florida, high school shooting. It also raised the age of sale of all firearms to 21.
Walmart says it has not sold "modern sporting rifles" -- such as the kind that was used by the Florida shooter -- since 2015. "We also do not sell handguns, except in Alaska where we feel we should continue to offer them to our customers," the company said.
"We take seriously our obligation to be a responsible seller of firearms and go beyond Federal law by requiring customers to pass a background check before purchasing any firearm," the company said.