A waste collecting device, comprising a frame, a waste buffer box, a negative pressure flow-equalizing box and a waste collecting box, wherein the waste buffer box is arranged on an upper part of the frame, the waste buffer box is provided thereon with a waste pipeline the waste pipeline is configured to extend to an operation station to make generated waste transported to the waste buffer box, the negative pressure flow-equalizing box is arranged on a top of the waste buffer box, the negative pressure flow-equalizing box is communicated with the waste buffer box, the negative pressure flow-equalizing box is configured to equalize gas flowing in from the waste buffer box, and a negative pressure pipeline is arranged on the negative pressure flow-equalizing box, the negative pressure pipeline is configured to draw out gas in the negative pressure flow-equalizing box, and the waste collecting box is movably arranged at a lower part of the frame and is selectively communicated with the waste buffer box for collecting waste dropped from the waste buffer box, wherein the waste collecting device further comprises a waste compressing box disposed between the waste buffer box and the waste collecting box, the waste compressing box is selectively communicated with the waste buffer box, the waste compressing box is selectively communicated with the waste collecting box, and the waste compressing box is configured to temporarily store the waste dropped from the waste buffer box and compress the waste, characterized in that a negative pressure branch pipeline is further provided on the negative pressure pipeline, and the negative pressure branch pipeline communicates with the waste compressing box, a compression flow-equalizing box is further arranged on the waste compressing box, a second flow-equalizing plate is arranged between the compression flow-equalizing box and the waste compressing box, a plurality of second flow-equalizing holes are provided on the second flow-equalizing plate, and the compression flow-equalizing box communicates with the waste compressing box through the plurality of second flow-equalizing holes, and the second flow-equalizing plate and the negative pressure branch pipeline are arranged at interval. wherein the waste collecting device further comprises a waste compressing box disposed between the waste buffer box and the waste collecting box, the waste compressing box is selectively communicated with the waste buffer box, the waste compressing box is selectively communicated with the waste collecting box, and the waste compressing box is configured to temporarily store the waste dropped from the waste buffer box and compress the waste, characterized in that a negative pressure branch pipeline is further provided on the negative pressure pipeline, and the negative pressure branch pipeline communicates with the waste compressing box, a compression flow-equalizing box is further arranged on the waste compressing box, a second flow-equalizing plate is arranged between the compression flow-equalizing box and the waste compressing box, a plurality of second flow-equalizing holes are provided on the second flow-equalizing plate, and the compression flow-equalizing box communicates with the waste compressing box through the plurality of second flow-equalizing holes, and the second flow-equalizing plate and the negative pressure branch pipeline are arranged at interval.