Sterilization is a crucial step during vegetable merchandise producing process.Javel water is a know-how sterilization production and often used in the vegetable sterilization process.But the sterilization power is greatly influenced by pH of the solution.It is well known that Javel water will have the max sterilization power when pH falls in 5 through 7.But in fact,it is a pity that the entire vegetable producing factories in China use Javel water keeping the pH above 7.The present paper analyzes the sterilization principle of such Javel water named weak acid hypochlorous solution.And three different such solution produce methods are also described.