The invention belongs to the technical field of agricultural machinery, and relates to a small-size chained opium poppy harvesting machine. The opium poppy harvesting machine comprises a harvesting bin, a harvesting table, a transmission system, a conveying device and a wheel type chassis; the harvesting table comprises a reciprocating type cutter arranged at the front end of a bottom plate, multiple harvesting monomers arranged in parallel and a harvesting table driving shaft; each harvesting monomer comprises two bilaterally symmetrical parts, and the left part and right part of each harvesting monomer comprise dividers, guiders, drawing rollers, vertical supporting plates, clamping chains, disc knifes and horizontal mounting plates of the clamping chains respectively; the conveying device comprises a spiral conveyor; the transmission system drives the spiral conveyor, the harvesting table and the reciprocating type cutter. The small-size chained opium poppy harvesting machine has the advantages of being able to adapt to the growth characteristics of opium poppy, meeting the harvesting requirement of the opium poppy, saving manpower and material resources, and improving the laborproduction efficiency.