The invention relates to a synthetic method of 
pyridinium hydroxy propyl sulfobetaine. The synthetic method comprises the following steps: sufficiently dissolving hydrosulphite or pyrosulfite in water at normal temperature, adding 
sodium sulfite as an auxiliary sulfonating agent to adjust the pH value of the 
system to be 5.2-5.5, and then adding polyether F-6 as a catalyst; then adding a complexing agent, controlling the environment conditions, adding 
epichlorohydrin, and carrying out loop-opening reaction to obtain 3-chloro-2-hydroxy propanesulfonate; adding 
pyridine to the 
system, controlling the temperature to carry out 
reflux reaction, adding 
triethylamine as an 
impurity removing agent, reacting for 1 hour, then dehydrating and decoloring, adjusting the pH to 2-5, and adding 4-hydroxyl-2, 2, 6, 6-tetramentylniperidine-1-
oxygen radical as a stabilizer and a 
vitamin C derivative to obtain an 
aqueous solution of the 
pyridinium hydroxy propyl sulfobetaine. The 
pyridinium hydroxy propyl sulfobetaine synthesized by the synthetic method is produced by adopting a one-pot method, which accords with the 
electroplating industry development demands at present; the pyridinium hydroxy propyl sulfobetaine is low in 
impurity content, good in appearance and low in production cost.