A preparation method of a nanotube hierarchically structured lithium titanate, wherein the method comprises the steps of: S1. dispersing a titanium source into an aqueous solution containing lithium hydroxide and hydrogen peroxide and stirring to obtain a mixed solution; preferably, the titanium source is selected from one or more of titanium ethoxide, titanium isopropoxide, titanium propoxide, tetrabutyl titanate, titanium glycolate, titanium glyceroxide, titanium sulfate, titanium oxysulfate, titanium tetrachloride, titanium tetrafluoride, ammonium fluorotitanate, titanium nitride, titanium oxide, metatitanic acid, and orthotitanic acid; S2. subjecting the mixed solution obtained in step S1 to a reaction by heating to obtain a precursor having a nanowire-like structure; wherein, the reaction by heating in step S2 is carried out by heating the mixed solution to a temperature of 60°C to 100°C; and, the duration of the reaction is 0.5h to 24h; S3. subjecting the precursor having a nanowire-like structure obtained in step S2 to separation and drying; preferably, the drying in step S3 is carried out at a temperature of 20°C to 80°C; S4. subjecting the precursor having a nanowire-like structure after separation and drying to a low-temperature annealing treatment; the low-temperature annealing treatment in step S4 is carried out at a temperature of 120°C to 200°C for a duration of 0.5h to 12h; S5. subjecting the precursor having a nanowire-like structure after the low-temperature annealing treatment to a liquid thermal reaction to obtain the nanotube hierarchically structured lithium titanate; wherein, the liquid thermal reaction is carried out at a temperature of 80°C to 150°C for a duration of 1h to 24h; the liquid thermal reaction is carried out by dispersing the precursor having a nanowire-like structure after the low-temperature annealing treatment in step S4 into water or a lithium hydroxide aqueous solution; the lithium hydroxide aqueous solution has a concentration of 0.05mol/L to 0.3mol/L. S1. dispersing a titanium source into an aqueous solution containing lithium hydroxide and hydrogen peroxide and stirring to obtain a mixed solution; preferably, the titanium source is selected from one or more of titanium ethoxide, titanium isopropoxide, titanium propoxide, tetrabutyl titanate, titanium glycolate, titanium glyceroxide, titanium sulfate, titanium oxysulfate, titanium tetrachloride, titanium tetrafluoride, ammonium fluorotitanate, titanium nitride, titanium oxide, metatitanic acid, and orthotitanic acid; S2. subjecting the mixed solution obtained in step S1 to a reaction by heating to obtain a precursor having a nanowire-like structure; wherein, the reaction by heating in step S2 is carried out by heating the mixed solution to a temperature of 60°C to 100°C; and, the duration of the reaction is 0.5h to 24h; S3. subjecting the precursor having a nanowire-like structure obtained in step S2 to separation and drying; preferably, the drying in step S3 is carried out at a temperature of 20°C to 80°C; S4. subjecting the precursor having a nanowire-like structure after separation and drying to a low-temperature annealing treatment; the low-temperature annealing treatment in step S4 is carried out at a temperature of 120°C to 200°C for a duration of 0.5h to 12h; S5. subjecting the precursor having a nanowire-like structure after the low-temperature annealing treatment to a liquid thermal reaction to obtain the nanotube hierarchically structured lithium titanate; wherein, the liquid thermal reaction is carried out at a temperature of 80°C to 150°C for a duration of 1h to 24h; the liquid thermal reaction is carried out by dispersing the precursor having a nanowire-like structure after the low-temperature annealing treatment in step S4 into water or a lithium hydroxide aqueous solution; the lithium hydroxide aqueous solution has a concentration of 0.05mol/L to 0.3mol/L.