To provide a load balancing apparatus that properly distributes server load.

A load balancer 10 distributes input packets among servers registered as target servers in an allocation table 21 so as to impose a uniform load on the servers. A response measuring device 11 measures a response time from arrival times of a packet addressed to a server and a response packet from the server which pass through a switch SW(2). When there is a server whose response time is greater than a predetermined value, it is determined that the server is overloaded, and the load balancer 10 is instructed to exclude the server from the load balancing.