The invention discloses an automobile lock ring type synchronizer. The automobile lock ring type synchronizer comprises a first shaft, a second shaft, a joint sleeve, a spline shaft, a first joint tooth ring, a second joint tooth ring, a positioning pin, a sliding block and a lock ring. The second shaft is arranged on one side of the first shaft and communicates with the first shaft. The first shaft is provided with the first joint tooth ring, and the second shaft is provided with the second joint tooth ring. The lock ring is arranged between the first joint tooth ring and the second joint tooth ring and internally provided with the sliding block. The sliding block is connected with the spline shaft. The spline shaft is sleeved with the joint sleeve. The automobile lock ring type synchronizer is simple and reasonable in structural design, components are used in cooperation, integral running stability of the structure is guaranteed, and the space area is greatly saved; and the first shaft, the second shaft and the spline shaft are cast through stainless steel into an integrally-formed structure, the anti-corrosion performance of the stainless steel is extremely good, strength is high, and the service life of the components is greatly prolonged.