The invention discloses a low-resilience liquid accelerator for shotcrete and a preparation method thereof. The accelerator is prepared from the following raw materials in percent by mass: 20%-40% of sodium hydroxide, 25%-40% of aluminium hydroxide, 3%-10% of a synergist, 0.5%-2% of a setting accelerator, 0.003%-0.02% of a viscosity adjusting agent, and the balance water, wherein, the synergist is sodium silicate, the setting accelerator is an alcohol amine substance, and the viscosity adjusting agent is potassium chromate or sodium nitrite. The preparation method comprises the following technical steps: adding sodium hydroxide and the synergist into a reaction kettle, adding water, and starting an agitator and a heater; keeping the temperature after the temperature reaches a set temperature, adding aluminium hydroxide, and reacting with the constant temperature; adding the viscosity adjusting agent, stirring, heating, reacting with a constant temperature, then stopping heating, and naturally cooling; and adding the setting accelerator after the reaction system is cooled, and cooling to room temperature, so as to obtain the accelerator. The accelerator is short in setting time, low in resilience and moderate in viscosity, generates a little sediment, has good cement adaptability, and the preparation method for the accelerator is simple, practicable and energy-saving.