The invention provides a robot-based cleaning and dust collecting device which is provided with a rolling brush. Walking wheels are arranged on the two sides of the rolling brush. The robot-based cleaning and dust collecting device includes a push rod, a turning arm, and two dust collecting units symmetrically distributed on the two sides of the rolling brush. Each dust collecting unit includes adust blocking beam and a dust collecting box, and the dust blocking beam is arranged in the dust collecting box. The dust blocking beams are arranged in the dust collecting boxes and near the rollingbrush so as to clean the dust on the rolling brush and store the dust in the dust collecting boxes. The dust collecting boxes are fixedly connected with the turning arm. The push rod is arranged abovethe turning arm in a tangent manner so that the turning arm can rotate and drive the dust collecting boxes to rotate to dump the dust under the action of the push rod. The dust on the surface of a photovoltaic panel can be collected, and the collected dust can be dumped when a photovoltaic cleaning robot reaches a stop position. Therefore, secondary pollution caused by dust fall can be avoided, and the cleaning effect can be improved.