Communication method in ad-hoc network

A communication method in an Ad-hoc network is provided to minimize energy used for assigning data bits to be transmitted to a secured channel. A communication method using an Ad-hoc network comprises the following steps of: setting up a negotiation channel between the first node and the second node for transmitting/receiving data and at least one data transmission channel; and detecting a common unavailable channel between the first node and the second node among the set data transmission channel; transmitting through the detected channel. The channel detection step comprises the following processes. The first node provides information about its unavailable channel to the second node through the negotiation channel, and then receives information about the common unavailable channel, which is obtained by comparison between provided information and information about an unavailable channel of the second node, from the second node.