The invention discloses flexible glass and a preparation method thereof. The flexible glass is prepared from the following raw materials in parts by weight: 60.04 to 63.01 parts by weight of silicon dioxide, 16.7 to 21.5 parts by weight of aluminum oxide, 12.93 to 19.85 parts by weight of boric oxide, 2.43 to 14.19 parts by weight of calcium carbonate, 0.16 to 2.07 parts by weight of magnesium oxide, 0.5 to 2.74 parts by weight of strontium carbonate and 0.12 to 4.16 parts by weight of barium nitrate. The method comprises the following steps: 1, pouring raw materials into a mixer, and uniformly mixing to form a mixture; step 2, adding the mixture in the step 1 into a glass kiln through a batch feeder, heating to melt glass, clarifying the molten glass in a platinum feeding channel, and flowing the clarified glass into a stay tube tunnel; 3, drawing the molten glass into a long glass tube in a tube drawing tunnel by a traction tube drawing machine, wherein the interior of the tube drawing tunnel is in a polar atmosphere; step 4, transversely and longitudinally cutting the glass tube by using a laser cutting machine according to specification requirements to form a glass sheet; and step 5, inspecting the glass sheet to prepare a flexible glass product.