The invention discloses an air inlet shaft air amount multiplication and heating anti-freezing device. Through a non-closed gap on the inner side of an annular shell body of the device, positive-pressure hot air flow blows downwards into a shaft along a wall face, a negative-pressure zone can be formed above the shell body through the hot air flow with high speed, shaft opening air is promoted to flow into the shaft and carries out even heat exchanging with the shaft, and accordingly the purpose of shaft freezing resistance is achieved. The whole device is fixed on the wall face near the shaft opening through an embedding and anchoring structure, hot air blown out from the shell body gap is tightly attached to the wall face, and the phenomenon that hot air is directly squeezed out from a hot air channel, so that the wall face is not heated evenly, and freezing happens is avoided. According to the device, the injecting principle is used, hot air resistance or ventilation resistance can be lowered, at the shaft, due to natural air pressure effect, air amount is obviously lowered, press-in air amount is increased, and air around the shaft opening can be effectively driven to flow to achieve the purpose of increasing of total air inlet amount by multiple times. The device is simple in structure and convenient to maintain, the shell body is made of high-temperature-resisting, corrosion-resisting, inflaming retarding and anti-static materials, safety is high, and the device is very suitable for promotion and application in a high cold mine zone where shaft freezing can happen easily.