Automobile vacuum brake booster

The utility model relates to the vehicle braking technology field, in particular to a vehicle vacuum brake booster. The utility model solves the problems of the prior vehicle vacuum brake booster that the braking effect is poor, and simultaneously the dustproof and muting components are difficult to be replaced and cleaned, etc. Because the air inlet cross section of the rear casing of the air chamber is small, and the air inlet flow capacity is small. The utility model comprises the rear casing of the air chamber and a dust cover, one end of which is sealed and fixed with the rear casing of the air chamber. A push rod connected with a controlling valve assembly penetrates through and is arranged in the rear casing of the air chamber. The other end of the dust cover is sealed and fixed with the push rod, an air inlet opening is arranged on the dust cover, and a sponge filtering layer sleeved on the push rod is wrapped on the outer surface of the dust cover and at the position where the air inlet opening is ar