A single-fiber fault response method and apparatus, capable of quickly responding to a single-fiber fault and improving a bidirectional forwarding detection performance. The method comprises: a second apparatus sends, when detecting a signal loss in a process that the second apparatus and a first apparatus perform bidirectional forwarding detection (BFD), a remote fault (RF) signal to the first apparatus; and the first apparatus makes, after receiving the RF signal, a switching decision according to a first association table pre-set in the first apparatus, the first association table comprising a corresponding relationship between a port of the first apparatus, BFD session information and protection group information.
