An automatic testing apparatus (200) includes a transmission floor (210), a board (220), a stopping unit (230), and a testing device (260) beside the transmission floor. The transmission floor includes a plurality of rollers (211) positioned at two sides thereof. The board positioned on the rollers includes an I/O (input/output) circuit (222) and a first connector (265) electrically connected to the I/O circuit. The testing device includes a second connector (225) matchable with the first connector. The I/O circuit is used to electrically connect to an electronic device to be tested, such as an LCD (280). The stopping unit is positioned at the transmission floor for stopping the board moving. An automatic testing method using the automatic testing apparatus for testing an electronic device is also provided. The efficiency of the automatic testing apparatus is high.