The invention discloses a novel continuous large dropwise adding technological method in sodium hydrosulfite production. An original technological method in sodium hydrosulfite production has the disadvantages that a backing material needs to be prepared, dry sodium formate needs to be added at twice, for the first time, mother liquid is mixed with a certain amount of dry sodium formate so as to serve as the backing material, and for the section time, a certain amount of water is mixed with the dry sodium formate, then the dry sodium formate is heated and molten by using vapor and is used for large dropwise addition. The novel continuous large dropwise adding technological method is characterized in that all dry sodium formate, mother liquid and water are added at a time so as to prepare suspension liquid, and the original interval 'large dropwise adding' is changed into the continuous 'large dropwise adding'. The novel continuous large dropwise adding technological method has the advantages that the production efficiency is improved by 200%, the stability of the quality of the sodium hydrosulfite product is aslo substantially improved, the production is easy to control, the particle size, the yield and the quality of the product are ensured, the working procedures of preparing the backing material and adjusting values are omitted, all the dry sodium formate, the mother liquid and the water are added at a time so as to prepare suspension liquid, the heating melting is not needed, the addition amount of the water is accurate, the using amount of vapor is reduced, and the time is saved. The production efficiency is substantially improved, and the quality and the consistency of the sodium hydrosulfite product are ensured.