The invention discloses an embedded buffering closing-assisted locking mechanism for a large-sized armrest. The embedded buffering closing-assisted locking mechanism for the large-sized armrest comprises an armrest; the armrest comprises an armrest framework assembly and a hinge assembly; the embedded buffering closing-assisted locking mechanism for the large-sized armrest further comprises a torque hinged support assembly and a locking and unlocking assembly, wherein the torque hinged support assembly comprises a torque hinged support connecting pipe and a first torque hinged support which isfixed at one end of the torque hinged support connecting pipe; the two ends of the torque hinged support connecting pipe are fixed on the hinge assembly after correspondingly penetrating through thetwo opposite side walls in the armrest framework assembly; the hinge assembly is fixed on a seat framework; the armrest framework assembly can rotate around the torque hinged support connecting pipe;the locking and unlocking assembly is mounted on the armrest framework assembly; after the armrest is in a folded state, the locking and unlocking assembly locks the first torque hinged support so asto lock the armrest framework; and after the locking and unlocking assembly unlocks the first torque hinged support, the armrest can rotate and turn over around the torque hinged support connecting pipe. According to the embedded buffering closing-assisted locking mechanism for the large-sized armrest, as the locking and unlocking mechanism is arranged in the armrest, small space is occupied, andthe application range is wide.