The present invention is related to a portable electronic assay device, a portable assay device and a kit thereof. The portable electronic assay device is used for determining a result of an assay performed using a test strip comprises a casing, an optical module, a light detector, and a processor. The casing comprises a transmissive part. The optical module emits a detecting light signal and display light signal. The detecting light signal is illuminated to the test strip and the display light signal is illuminated to the transmissive part. The light detector detects light from the test strip so as to obtain a detecting signal. The processor receives the detecting signal compared with a default value so as to obtain an assay result. The assay result is displayed on the transmissive part. Therefore, it provides simple structure of the assay device for displaying the assay result rapidly and correctly.
