The nanoindentation test and geometry measurement have been conducted to evaluate the hardness and geometry changes of bonded Au ball bonds towards the changes of the selected wire bonding parameters namely bonding power, bonding time and bonding force. Three indentations were made on the bonded ball bonds to evaluate the variation of hardness properties with the location of indentation. It was noted that the increase of bonding or ultrasonic power will increase the hardness value for the indentations 1 and 3 located at the periphery of bonded ball bonds. The increase of bonding power also increased the deformation of bonded ball bonds. It was also shown that the increment of bonding time will increase the hardness value across the bonded ball bonds in almost even distribution. The application of the bonding force in the wire bonding process has the least effect on the hardness and geometry changes on the bonded ball bonds.