The invention belongs to the field of pharmaceutical chemistry, and discloses a purification method for a crystal of insulin or an analogue thereof. The purification method comprises: adopting an easy-volatilizing and low-toxicity organic solvent to rinse and leach an insulin crystal or an insulin analogue crystal in a short time so as to completely remove the trace poor-volatility and high-toxicity organic solvent remaining in the crystal, and drying to completely remove the good-volatility organic solvent introduced during rinsing and leaching after completing leaching so as to solve the problem of residue of the difficultly-volatilized organic solvent in the crystal. According to the purification method, the operation is simple and quick, the purified insulin crystal or insulin analogue crystal finished product has characteristics of high crystal purity, low solvent residue, uniform particle, good dispersity, and easy storage and sub-package compared with the untreated crystal.