A channel access method under spatial reuse, comprising: an intercepting station detecting a first radio signal of a third-party station, updating a local network allocation vector and/or a response indication deferral; when not detecting a second radio signal of the third-party station within a preset time interval Δt after an end of the intercepting station detecting the first radio signal of the third-party station, determining that the second radio signal of the third-party station meets a spatial orthogonal condition and triggering a channel contention access procedure, wherein the triggering a channel contention comprises: saving a state of an existing random backoff procedure; starting a new random backoff procedure and contending for a channel to initiate a data transmission; and then completing the data transmission within a duration indicated after updating; wherein, when what is updated is the local network allocation vector, the duration indicated after updating is: the duration indicated by the updated local network allocation vector; when what is updated is the response indication deferral, the duration indicated after updating is: a duration indicated by the updated response indication deferral; when what is updated are the local network allocation vector and the response indication deferral, the duration indicated after updating is: the duration indicated by the updated local network allocation vector; or a longer one of durations indicated by the updated local network allocation vector and the updated response indication deferral; wherein, the first radio signal is transmitted in an omnidirectional mode; the second radio signal is transmitted in a directional or sectorization or beamforming mode; at expiry of a timer indicated by the updated local network allocation vector or the updated response indication deferral, the intercepting station resuming the state of the random backoff procedure saved during the triggered channel contention access procedure as the state of the current random backoff procedure. an intercepting station detecting a first radio signal of a third-party station, updating a local network allocation vector and/or a response indication deferral; when not detecting a second radio signal of the third-party station within a preset time interval Δt after an end of the intercepting station detecting the first radio signal of the third-party station, determining that the second radio signal of the third-party station meets a spatial orthogonal condition and triggering a channel contention access procedure, wherein the triggering a channel contention comprises: saving a state of an existing random backoff procedure; starting a new random backoff procedure and contending for a channel to initiate a data transmission; and then completing the data transmission within a duration indicated after updating; wherein, when what is updated is the local network allocation vector, the duration indicated after updating is: the duration indicated by the updated local network allocation vector; when what is updated is the response indication deferral, the duration indicated after updating is: a duration indicated by the updated response indication deferral; when what is updated are the local network allocation vector and the response indication deferral, the duration indicated after updating is: the duration indicated by the updated local network allocation vector; or a longer one of durations indicated by the updated local network allocation vector and the updated response indication deferral; wherein, the first radio signal is transmitted in an omnidirectional mode; the second radio signal is transmitted in a directional or sectorization or beamforming mode; at expiry of a timer indicated by the updated local network allocation vector or the updated response indication deferral, the intercepting station resuming the state of the random backoff procedure saved during the triggered channel contention access procedure as the state of the current random backoff procedure.