Disclosed are an acetylsalicylic acid derivative, i.e. a 2-(diethylamino)ethyl 2-acetoxy-benzoate hydrochloride crystal, and a preparation method and use thereof. The X-ray powder diffraction (XRPD) pattern of the crystal has characteristic peaks at the following 2θ angle: 11.0°±0.2°, 20.6°±0.2°, 25.1°±0.2°, 8.2°±0.2°, 16.5°±0.2°, 13.4°±0.2°, 25.4°±0.2°.