A preparation method for camellia extract includes the following steps: 1) Removing impurities from fresh camellia and/or fresh camellia buds, cutting the fresh camellia and/or fresh camellia buds into small sections for use as raw materials 2) Placing a certain quantity of raw materials into a ultrasonic vessel, adding in a solvent having a mass ratio of 1:3 to 1:30 to form a mixture, uniformly stirring the mixture, and then adding in a certain amount of inorganic acid and/or organic acid to adjust the pH value to 1.3 to 3.0, then soaking the raw materials for 10 minutes to 30 minutes 3) Performing ultrasonic treatment for 30 minutes to 60 minutes, controlling the ultrasonic frequency to be 20 KHz to 25 KHz, the ultrasonic power to be 1000 W to 2000 W, the ultrasonic temperature to be 15° C. to 50° C., then performing filtration, sterilization and detection to obtain camellia extract.
