The exchange says the move will help to "ensure fit and proper" behavior by its employees.
It comes after the group published a code of conduct in April, which sought to clamp down on harassment and behavior that was "threatening, humiliating or disruptive."
A spokesperson for the exchange said Friday that it has "broad powers" to ensure proper behavior on the Ring, and that its members have policies in place to police their employees.
"The LME appreciates the high standards upheld by its members, and has formalized the general position that Ring-based personnel should not consume any alcohol prior to conducting business," the spokesperson said.
The exchange is not the only financial institution in London to crack down recently on day drinking.
Lloyd's of London said in April that it will bar people believed to be drunk from its premises. Anyone who attempts to enter the insurance market while under the influence will have their security pass confiscated.
Open outcry, a face-to-face style of trading that has been mostly phased out in favor of electronic alternatives, features shouting, hand signals and intense communication between buyers and sellers.
The Ring at the LME is the last surviving example in Europe of such a floor, usually known as a "pit" an environment long associated with domineering and alpha behavior.
"When working in the global metals markets, everyone should feel welcome, safe and able to participate," the group said in its recently introduced code, which warned against "threat of intimidation or harassment of any kind."
Being authorized to enter the Ring marks the highest level traders at the exchange can reach, with many waiting years until they are permitted to do so.