The invention relates to a method for producing sheath-core type low-melting point polyester staple fiber. The method is characterized in that a sheath layer is low-melting point polyester fused mass which is obtained by direct spinning of fused mass; a core layer is regular PET polyester fused mass which is obtained by a regular PET chip spinning technology; two fused masses are measured by each measuring pump and then enter into a composite spinning component; fused mass sprayed from a spinning board of the composite component is cooled, coiled, bunched, stretched, set, cut and packed; and the sheath-core type low-melting point polyester staple fiber can be obtained. The production method has stable operation and good product quality, and the produced sheath-core type low-melting point polyester staple fiber can be applied in the industries of nonwoven fabric, flocking, composite material, etc.