A method for controlling functions of a Management Device (MD) included in a home network is provided. The method for controlling the functions of the MD by a Control Device (CD) in a home network system including the CD for controlling functions of an Electronic Device (ED) connected to a home network and the MD, the functions of which are managed by the CD, includes diagnosing at least one function performed by the MD; identifying information necessary to control the at least one function; and transmitting, to the MD, control information for controlling the at least one function, in consideration of the information necessary to control the at least one function.