The invention discloses a home-position air-captive sampler of hydraulic driving subjacent sediment, which comprises the following parts: casing component, knife head, rear lifting block, liner component, sealing ball valve and hydraulic driving device, wherein the knife head is set on the bottom of casing component; the rear lifting block is set on the top of casing component; the liner component is set in the casing component to slide along the inner wall; the sealing ball valve is connected on the casing component through flange; the hydraulic driving device is set on the casing component to switch the ball valve; the liner component contains at least two liner units to store the sample sectionally, which is convenient to know the stratified structure of sediment. The invention displays high automatic degree and good reliability to guarantee the strict sealing, which improves the success rate of sampling. |