To provide a weak light detection system and weak light detection method that enable a simple configuration to detect weak light of an object at a high S/N ratio.SOLUTION: A control unit 15 of a weak light detection system is configured to apply an encoding system to a prescribed transmission information series by an error correction code generation unit 151, and make a generated error correction code series modulate excitation light with which an excitation light irradiation unit 171 irradiates a test piece. A light reception code series identification unit (an A/D converter 153) is configured to identify a light reception code series on the basis of a change in light reception intensity in a light reception unit 172 receiving light to be excited in the test piece using an excitation light irradiation pattern. A signal processing unit 154 is configured to obtain a decode information series by applying a decoding system of the error correction code to the light reception code series, collate the transmission information series with the decode information series, and when the transmission information series is consistent with the decode information series, determine that light emission corresponding to the excitation light irradiation pattern is performed from the test piece.SELECTED DRAWING: Figure 3
WEAK LIGHT DETECTION SYSTEM, AND WEAK LIGHT DETECTION METHOD