The drop was the biggest one-day loss since Jan. 9 for the maker of Mexican beers like Corona and Modelo.
On Thursday night, Trump tweeted will impose a 5% tariff on all goods coming from Mexico starting June 10 "until such time as illegal migrants coming through Mexico, and into our Country, STOP."
The White House then said in a statement that levies on Mexican imports would increase up to 25% if immigration issues along the U.S.-Mexico border persisted. Mexico President Andres Manuel Lopez Obrador responded to the threat in a letter to Trump, saying: "Social problems cannot be resolved with taxes or coercive measures."
Tariffs on Mexican goods would dent Constellation Brands' stock and bottom line. According to Morgan Stanley, about 75% of its beer portfolio is "entirely imported" from Mexico. The bank also notes that a 5% tariffs on Mexican goods would shave off nearly 4% from the company's overall bottom line. A 25% levy, meanwhile, would slash Constellation Brands' profit by 19%.
BMO Capital Markets notes the impact could be bigger. An analyst at the bank estimates Constellation Brands imports 95%-to-98% of its beer from Mexico.
—CNBC's Frank Holland contributed to this report.