The utility model relates to an automobile safety belt buckling detecting device which is characterized by comprising an automobile safety belt buckle with a non-transparent spring bolt, a central processing unit, a detecting unit and an alarm unit. The central processing unit is connected with the detecting unit and the alarm unit. The detecting unit comprises a light-emitting diode and a photosensitive resistor, wherein the light-emitting diode and the photosensitive resistor are oppositely arranged on the inner side of the automobile safety belt buckle. When the belt buckle is buckled by the non-transparent spring bolt, the photosensitive resistor and the light-emitting diode which are arranged on the inner side of the belt buckle are separated, and the central processing unit can control the alarm unit to give out alarm to remind a driver to buckle the safety belt. The automobile safety belt buckling detecting device is simple in structure, low in cost and high in practicability.