The present disclosure relates to a dust collecting device including an air inflow part having a suction flow path through which air is introduced, a dust separating part configured to separate dust from the air introduced through the air inflow part, a dust bag configured to store the dust separated by the dust separating part, a bag support part configured to accommodate the dust bag, a housing configured to accommodate the bag support part and the dust separating part therein, a suction motor configured to provide a flow force of the air, and a connection part including a connection flow path configured to guide the air, which has passed through the dust separating part, to the suction motor, and a bypass flow path configured to connect the bag support part and the suction motor, thereby enabling a user to empty a dust bin only by removing the dust bag.