The man was with a group of four other wingsuit enthusiasts on Saturday at the Hinterrugg mountain near Walenstadt, police said in a news release.
The five jumped from a spot known as Sputnik, according to the release.
The Mexican lost control and opened his parachute too late, police indicated.
He died from the force of landing in a meadow.
When a Rega emergency rescue team arrived by helicopter on the scene the victim was already dead.
Hinterrugg, a 2,306-metre peak in the Appenzell Alps, is known as a popular spot for base jumping and wingsuit flying.
The Mexican's death was the latest in a series of wingsuit fatalities, coming two weeks after renowned Australian winsguit flyer Alex Duncan died after crashing into a mountainside in the canton of Valais.
Duncan, 26, was killed on September 2nd after jumping from the summit of the 2,243 Croix de Fer mountain.
He hit a rock face after going off track.
Wingsuit flying is a high-risk sport involving jumping off cliffs or out of aircraft while wearing a suit designed to break a fall, allowing the user to “fly” before opening a parachute to land.
British wingsuit diver and stuntman Mark Sutton — best known for parachuting into the London 2012 Olympics opening ceremony dressed as James Bond — died in August 2013 when he crashed into a mountain ridge in Valais after jumping from a helicopter.