A nucleic acid amplification device and a nucleic acid inspection system

Provided is a nucleic acid amplification device that reduces a decrease in detection accuracy associated with a temperature change. The nucleic acid amplification device 100 includes a first housing 10, a holder 31 holding a reaction container 110 installed from above the first housing 10, a temperature adjustment unit 40 provided inside the first housing 10 and adjusting a temperature of a sample stored in the reaction container 110 held by the holder 31, A second housing 20 provided outside the first housing 10 and covering the holder 31 so as to open and close, a light detection unit 53 provided inside the second housing 20 and detecting an optical signal accompanying nucleic acid amplification from a reaction container 110 held by the holder 31, And a control unit that can control Figure 1