The invention discloses a storage tank margin plate anti-corrosion sealing structure and a manufacturing method thereof. The manufacturing method comprises the steps of preparing a material for manufacturing a sealing structure; cleaning a storage tank device before sealing; filling a non-cured antiseptic plaster into gaps of a margin plate and a cement ring beam; coating asphalt grout on the surface of the non-cured antiseptic plaster, the surface of the margin plate and the surface of the cement ring beam; comprehensively coating a cured elastic weather-proof sealant on the asphalt grout. The storage tank margin plate anti-corrosion sealing structure can be well bonded with the tank wall and the cement ring beam to form a complete anti-corrosion sealing system and has good elasticity, weather resistance and anti-corrosion capacity, and the problem of invalid anti-corrosion sealing caused by deformation of the outer margin plate of the storage tank and environment factors can be avoided.