Dust discharge channel connecting assembly and electric circular saw

The utility model discloses a dust discharge channel connecting assembly and an electric circular saw, the dust discharge channel connecting assembly is used for connecting an electric tool and a dust discharge channel, and comprises a clamping end arranged at a dust discharge pipe interface of the dust discharge channel and a lock catch end arranged at the upper edge of a dust discharge port on the electric tool and butted with the clamping end; the clamping end is provided with a plurality of radial protrusions, and the protrusions extend in the direction close to the dust discharging opening. The lock catch end is provided with a lock catch unit matched with the protrusion to limit the dust discharging pipe to be separated from the dust discharging opening, and the lock catch unit comprises a guide part, a steering part and a lock catch part arranged at the joint of the guide part and the steering part, the lock catch part is provided with a guide face for guiding the protrusion to enter the steering part