The invention relates to a high-adaptability storage tank once sealing method, and mainly solves the problem of weaker sealing effect when a storage tank is deformed in the prior art. The high-adaptability storage tank once sealing method comprises a sealing rubber block (1), sealing liquid (2), a sealing strip (3) and a fixed bolt (4), wherein the sealing rubber block (1), the sealing liquid (2) and the sealing strip (3) are positioned between the tank wall of the storage tank and a floating disc; the bottom of the sealing rubber block (1) is contacted with a material stored in the storage tank, and the top is contacted with the sealing liquid (2); except for achieving a sealing effect, the sealing rubber block (1) has a support effect on the sealing liquid (2); the sealing rubber block (1) and the sealing liquid (2) are packed as a whole through the sealing strip (3), and are fixed on the floating disc of the storage tank through the fixed bolt (4); and the high-adaptability storage tank once sealing method for realizing the sealing between the floating disc and the tank wall preferably solves the problem, and can be applied to the storage tank sealing.