The invention relates to an air tightness test fixture, which comprises a storage seat, a driver, a push plate, an ejector rod and an elastic test assembly, and is characterized in that a groove is formed in the storage seat, the groove is provided with an opening, and a product to be tested is assembled at the opening of the groove; the driver is in transmission connection with the push plate, the ejector rod is fixedly connected to the push plate, the elastic test assembly is movably connected to the push plate, the push plate is arranged corresponding to the storage seat and suspended abovethe storage seat, and the driver drives the push plate to move in the direction close to or away from the storage seat to drive the ejector rod and the elastic test assembly to be close to or away from the storage seat; the elastic test assembly comprises a supporting rod, a rubber plug and an elastic piece, a through hole is formed in the push plate, and the supporting rod is assembled and fixedin the through hole and movably connected to the push plate; the rubber plug is arranged at the end, away from the push plate, of the supporting rod and used for sealing the through hole; and one endof the elastic piece abuts against the push plate, and the other end abuts against the end, provided with the rubber plug, of the supporting rod. The air tightness test fixture can carry out air tightness test on a product with a through hole.