The invention discloses an amphiprotic sulfonate type polymerizable surfactant and a synthesizing method thereof. The synthesizing method comprises the following steps: (1) adding 1mol of long-chain alkyl dimethyl tertiary amine and 1.2-2mol of allyl bromide into ethyl alcohol, and stirring for reacting for 7-48h under nitrogen protection condition at temperature of 40-80 DEG C so as to obtain long-chain alkyl dimethyl allyl bromide ammonium bromide; (2) adding 1mol of long-chain alkyl dimethyl allyl bromide ammonium bromide, 1.2-20mol of acrylonitrile into a three-neck boiling flask, controlling a reaction system to 0 DEG C, dropwise adding 1.2-20mol of fuming sulphuric acid, stirring for 0.5-2h, rising temperature to 20-50 DEG C, and reacting for 12-48h so as to obtain the amphiprotic sulfonate type polymerizable surfactant. The surfactant has good surface activity and good polymerization performance; according to the synthesizing method, the principle is reliable, the operation is easy and convenient, the cost is low, and purification and separation are easy, and thus the market prospect is wide.