The invention discloses a method for automatically identifying an HDMI (High Definition Multimedia Interface) chip of a set top box. The method comprises the following steps: acquiring an ID of a current HDMI chip; responding the ID to acquire a successful signal and acquiring a driving program corresponding to the ID of the current HDMI chip; responding the driving program to acquire the successful signal, and setting the current HDMI chip according to the driving program. The method disclosed by the invention has the advantages that by pre-storage of the driving program for multiple HDMI chips, after the set top box is started, whether the current HDMI chip is normal is automatically identified, the driving program matched with the HDMI chip is automatically searched and set, so that one set top box can be applicable to multiple types of HDMI chips; when a certain type of HDMI chip is damaged and the same type of chip can not be bought, other types of chips can be used for replacement, so that the experience of a user is enhanced.