The invention discloses a quick-frozen and fresh-keeping thousand-sheet tofu and a preparation method thereof. The thousand-sheet tofu comprises the following components in parts by weight: 13-15 parts of soybean protein isolate, 0.1-0.25 parts of glutamine transaminase, and cassava acetate 2-3 parts of modified starch, 5-8 parts of soybean oil, 0.3-0.6 parts of monosodium glutamate, 0.3-0.6 parts of white sugar, 0.4-0.7 parts of compound gum, 2.5-3.5 parts of duck egg white, 68-75 parts of water. The quick-frozen and fresh-keeping thousand-sheet tofu of the present invention uses soybean protein isolate, glutamine transaminase, cassava acetate modified starch, soybean oil and monosodium glutamate, white sugar, compound glue, and duck egg white as raw materials, and the obtained thousand-sheet tofu product maintains the original tofu Some are tender and fragrant, and have unique smoothness, crispness, good elasticity and toughness, and super water absorption capacity of soup; whether they are fried, fried, deep-fried, stewed or served with other condiments, they taste unique. ,Delicious.