The utility model relates to the technical field of sampling devices, and discloses a sampling device for large benthonic animals in a
water body, which comprises a sampling box, the top end of the sampling box is fixedly connected with a
handle, the side wall of the sampling box is provided with an opening, and the inner wall of the sampling box at the opening is hinged with a cover plate. A
grating plate is fixedly connected to the side wall of the sampling box, an
insertion cone is fixedly connected to the bottom of the sampling box, a groove is formed in the inner wall of the
insertion cone, a fixing rod is fixedly connected to the portion, located on the inner wall of the groove, of the
insertion cone, and the rod wall of the fixing rod is movably sleeved with an extension plate and a torsional spring. According to the utility model, the insertion cone is inserted into the
underwater sediment, so that the sampling box is attached to the
underwater, the sampling box is ensured to be stably placed at the
underwater, and meanwhile, the
torsion spring pushes the extension plate to extend into the underwater
sediment, so that the contact area of the insertion cone in the underwater
sediment is increased, and the anti-shaking effect of the sampling box is improved.