A silkworm cocoon overturn device, comprising a picking unit for taking out silkworm cocoons and an expansion unit matching the picking unit and expanding the silkworm cocoons. The picking unit comprises a rotatable picking turntable (b1) arranged perpendicular to the ground and multiple picking structures disposed on the surface of the picking turntable (b1) and arranged in an annular array. Each picking structure comprises a picking air cylinder (b2) and further comprises two opening/closing rods (b3). One end of each of the two opening/closing rods (b3) is pivotally connected to a power output rod of the picking air cylinder (b2), and the other end of each of the two opening/closing rods (b3) is circular arc-shaped. Each picking structure further comprises a tightening hoop (b4) sleeved on the two opening/closing rods. The tightening hoop (b4) is fixed to the picking air cylinder by means of a cross rod. Overturn is implemented by means of matching of the expansion unit after picking, and the efficiency is
