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Bovine bone was used as the raw material to extract collagen by the high-intensity pulsed electric fields. The optimal processing conditions were acquired by the single-factor experiments and the Box-Behnken experiment. The most yield of dissoluble collagen 16.21mg/mL was achieved under the following conditions: substrate concentration 1.0g/(100mL), pepsin concentration 3%, pH value 2.5, electric field intensity 21.98kV/cm, electric pulse number 7. The extracted collagen was identified by UV spectra that it was the pure collagen protein and did not contain other miscellaneous proteins. 