Abstract: The present invention related to an electronic assay apparatus and a testing method thereof for increasing efficiency and saving power. The electronic assay apparatus for determining a result of an assay performed using a test strip comprises two light sources, one detector and a microprocessor. The two light sources respectively illuminate light incident upon a test zone or a control zone of a test strip. The only one detector disposed between the two light sources and detects light reflected from the test zone and the control zone alternately. The microprocessor compares a calculating result value to only one threshold for showing a result.