A transmission mount for a vehicle may include a bracket which accommodates an insulator having an external core coupled with an internal core, and includes an upper housing that covers an upper portion of the insulator, and a plate that supports a lower portion of the insulator; and the external core which includes, based on the inserted internal core, a lower portion, an upper portion, both lateral portions, both bridge portions that support a body of the external core, and a lower main stopper formed on an upper surface of the plate, in which a space portion is formed in a body of the external core wherein a strut, which protrudes from a rear surface of an upper housing of the bracket, is inserted into the space portion, and internal wall surfaces of the space portion come into contact with an upper portion, a lower portion, and a front portion of the strut, respectively.