The invention relates to a novel leaching device and a using method and application thereof. The leaching device comprises a filter with an upward opening and a vacuuming device. The filter comprises a funnel with an upward opening and filter medium, a buoy is optionally arranged, and the vacuuming device comprises a guiding tube, a liquid storing tank and a vacuum system. The leaching device leads solid and liquid to move backwards in a leaching process, solid sediment settles downwards under gravity, the liquid is removed above through pumping, solid matters can be prevented from blocking the filtering medium, accordingly time is saved and filtering efficiency is improved.