A battery pack leakage detection system, comprising: a test container provided with a test cavity configured for accommodating the battery pack therein; a gas filling subsystem configured for filling an interior of the battery pack with a quantity of tracer gas; a gas stirring subsystem arranged in the test cavity and configured for stir the air in the test cavity, such that the leaked tracer gas that leaks out from the battery pack into the test cavity is accelerated to mix with the air in the test cavity for realizing the uniform distribution of the leaked tracer gas in the test cavity; and a test analysis subsystem configured for sampling the mixed gas in the test cavity and analyzing the sampled gas to obtain the content of the leaked tracer gas in the test cavity, so as to determine whether the sealing requirement of the battery pack is satisfied or not according to the content of the leaked tracer gas in the test cavity; wherein the test container is a closed box for housing the battery pack during test of the battery pack, characterized in that: a support frame is provided below the test container, and the test container is supported on the support frame; the test container is provided with a door at one lateral side thereof for the entrance and exit of the battery pack, the gas stirring subsystem comprises at least one stirring fan mounted to an inner surface of a top plate of the test container, a conveying mechanism is provided in the test cavity and arranged on an inner surface of a bottom plate of the test container, and the conveying mechanism is configured for conveying the battery pack to enter or leave the test cavity via the door. a test container provided with a test cavity configured for accommodating the battery pack therein; a gas filling subsystem configured for filling an interior of the battery pack with a quantity of tracer gas; a gas stirring subsystem arranged in the test cavity and configured for stir the air in the test cavity, such that the leaked tracer gas that leaks out from the battery pack into the test cavity is accelerated to mix with the air in the test cavity for realizing the uniform distribution of the leaked tracer gas in the test cavity; and a test analysis subsystem configured for sampling the mixed gas in the test cavity and analyzing the sampled gas to obtain the content of the leaked tracer gas in the test cavity, so as to determine whether the sealing requirement of the battery pack is satisfied or not according to the content of the leaked tracer gas in the test cavity; wherein the test container is a closed box for housing the battery pack during test of the battery pack, characterized in that: a support frame is provided below the test container, and the test container is supported on the support frame; the test container is provided with a door at one lateral side thereof for the entrance and exit of the battery pack, the gas stirring subsystem comprises at least one stirring fan mounted to an inner surface of a top plate of the test container, a conveying mechanism is provided in the test cavity and arranged on an inner surface of a bottom plate of the test container, and the conveying mechanism is configured for conveying the battery pack to enter or leave the test cavity via the door. a support frame is provided below the test container, and the test container is supported on the support frame; the test container is provided with a door at one lateral side thereof for the entrance and exit of the battery pack, the gas stirring subsystem comprises at least one stirring fan mounted to an inner surface of a top plate of the test container, a conveying mechanism is provided in the test cavity and arranged on an inner surface of a bottom plate of the test container, and the conveying mechanism is configured for conveying the battery pack to enter or leave the test cavity via the door.