A nucleic acid detection kit includes a detection chip, an electrophoresis box, and a barrier unit. The detection chip includes a channel and an outlet. The outlet is connected to the channel. The temperature-dependent barrier unit may be in a first state or a second state. The barrier unit is disposed on a side of the outlet close to the channel when the barrier unit is in the first state, so that the channel is disconnected from the electrophoresis box. The barrier unit is away from the outlet when the barrier unit is in the second state, so that the channel is connected to the electrophoresis box. A nucleic acid detection device including the nucleic acid detection kit is also disclosed. The nucleic acid detection device has a simple structure, which is portable, flexible, and convenient, and can be used at home.