In a radio communication system in which packet communications are carried out by setting up one or more connections between the radio base station and radio terminals, a radio base station or a radio terminal carries out the timeout control in which any packet that cannot be received completely through one connection within a timeout interval that is set in advance with respect to the one connection is regarded as lost, a change in a number of active connections that are currently carrying out communications with the radio base station is detected, and a new timeout interval is calculated and set with respect to each connection when the change in the number of active connections is detected.