Leak detector for filter

The invention discloses a leak detector for a filter. The leak detector comprises the to-be-detected filter, a gas source and pressure sensors, wherein the to-be-detected filter is placed on a supporting plate, a sealing cover is arranged on the supporting plate outside the to-be-detected filter, an elastic cushion is arranged between the lower end of the sealing cover and the supporting plate, an elastic piece is arranged between the to-be-detected filter and the lower top surface of the sealing cover, a first pressure sensor is communicated with the to-be-detected filter, a second pressure sensor is communicated with a cavity between the sealing cover and the to-be-detected filter, a second valve is arranged on a gas path between the sealing cover and the gas source, a first valve is arranged on a gas path between a gas cylinder and the gas source, and a piston rod of the gas cylinder is opposite to the top surface of the sealing cover. The leak detector has the significant advantages that detection is accurate, the detection efficiency is high, and the quality of the filter cannot be affected.