Fastener driving tool

A fastener driving tool includes a nose portion, a supply passage and a fastener supply mechanism. The nose portion includes an injection passage for injecting a fastener. The supply passage is connected to the injection passage. The fastener supply mechanism feeds connected fasteners to the injection passage. The fastener supply mechanism includes a feed member which advances and retreats in a feed direction and which oscillates in a direction to retreat from the supply passage. The feed member includes a feed tooth which feeds the fastener to the injecting passage by engaging with a rear portion of the fastener and an auxiliary tooth which is disposed on a foot side of the fastener to prevent the fastener from deviating from the injection passage. When the feed tooth of the feed member projects into the supply passage, the auxiliary tooth projects into the supply passage longer than the feed tooth.