Deep sea in-situ microorganism multi-stage collection system

The utility model discloses a deep sea in-situ microorganism multi-stage collection system which comprises a filter cartridge, a connecting pipe and a deep water pump, the filter cartridge comprises an end cover and a base which are detachably fixed, and a filter membrane is detachably fixed between the end cover and the base; the multiple stages of filter cartridges are arranged and are communicated front and back through connecting pipes; and a deep water pump is arranged behind the last stage of filter cartridge to absorb water. According to the utility model, multiple stages of filter cartridges are arranged, so that multiple layers of filter membranes which are originally complicated are separated; each stage of filter cartridge is provided with an independent filter membrane, and after the structure of the filter cartridge is simplified, the filter membrane can be extracted and quickly replaced by detaching the top cover, so that the use is convenient; a negative-pressure collecting system is arranged,