The invention relates to an automatic power failure device for electric power information communication. The automatic power failure device comprises a case, a wind-driven device, a transmission roller, a driven longitudinal rod, a movable contact and a static contact, wherein the case comprises a case main body, an upper roaring hole, a transverse arrangement screw hole, a lower rotating hole, a position limiting screw bolt, a first wiring hole, a second wiring hole, an upper position limiting plate and a lower position limiting plate; the wind-driven device comprises an external threaded shaft, a driving gear, a wind-driven fan blade, a position limiting screw nut and a longitudinal arrangement insertion hole; the transmission roller comprises a transmission mandrel, a driven gear and a transmission roller post; the driven longitudinal rod comprises an overhead plug, a bottom plug, a bias longitudinal rod and a manual lock; the movable contact comprises a contact body, a hinging lug boss and a hinging connecting rod; the static contact is connected with a second conducting wire; the second conducting wire penetrates out of the casing main body from the second wiring hole. The automatic power failure device for electric power information communication has the advantages that the automatic power failure can be realized under the strong wind effect; the power failure can also be realized through manual pressing. The invention also discloses a power failure method of the automatic power failure device.