Borzillo, currently managing director for Ericsson Australia, New Zealand and the Pacific Islands, will depart on 7 July to head up traffic technology vendor Tenix Solutions.
His replacement will be Australian Bill Zikou, who is current Ericsson's president of its South East Europe division. Zikou will take up the position on July 10.
"Zikou returns to Australia after five years serving as the head of Ericsson businesses in Greece, Yugoslavia, Romania, Moldova, Bulgaria, Cyprus, Albania and Malta," a statement e-mailed by Ericsson late Friday night said.
Zikou has also previously held executive positions in Ericsson's Australian business, including the chief operations officer position.
Zikou's appointment comes at a sensitive time for Ericsson in Australia. The company has been contracted by Telstra to replace its national CDMA mobile phone network with a controversial third-generation (3G) equivalent.
Another key local customer for the vendor is Hutchison. Ericsson has a large managed services deal with the mobile carrier and in the new year will upgrade the metropolitan network Hutchison shares with Telstra to the High-Speed Downlink Packet Access (HSDPA) mobile broadband standard.