A management server and a management method thereof are provided. The management server is connected to a switch on a trunk port. The switch is connected to a plurality of cloud appliances in different virtual local area networks (VLANs). The management severs operates a management system and a translation system for managing cloud appliances. The translation system is operated to modify the receiving data packet by converting the source MAC address or the source IP address and removing the VLAN tag, and to modify the transmitting data packet by converting the destination MAC address or the destination IP address and adding a VLAN tag.