Provided is a normally-closed type buffer tramcar retarder. The normally-closed type buffer tramcar retarder comprises a mounting base, a movable frame, a journal sticking mechanism, a trigger mechanism and a buffer mechanism, wherein the movable frame is installed inside the mounting base through stopping shafts and guiding base shafts, the movable frame can move forward and backward in the mounting base, one end of the movable frame abuts against the mounting base through buffer springs, the journal sticking mechanism is composed of journal sticking hooks, journal sticking hook rotary shafts and self-locking devices, and the trigger mechanism is composed of a trigger base, a trigger, an air cylinder and trigger base rotary shafts. The normally-closed type buffer tramcar retarder has the advantages that the structure is simple and compact, and compared with a tramcar blocking column, the occupied space is reduced and cost is low. Due to the fact that the movable frame and a fixed frame are connected through springs, buffer tramcar retard is achieved. Due to the fact that the normally-closed type buffer tramcar retarder is in a closed state all the time when in a normal condition, the requirement that a tramcar blocking device needs to be in a normally-closed state is met. Due to the fact that the normally-closed type buffer tramcar retarder can retard a rear axle of a tramcar, the tramcar is prevented from tipping.