Abstract: In this paper, the separation and purification of jellyfish polypeptide with Angiotensin-I converting enzyme (ACE) inhibitory activity by macroporous adsorption resin was studied from the perspective of molecular polarity. The enzymatic hydrolysates of jellyfish were taken as the research object, and three different types of macroporous resin HP20SS, SP20SS and SP207 were used to isolate and purify the ACE inhibitory peptide of jellyfish. The ACE inhibitory rate was used as the evaluation index, and the separation and purification process of ACE inhibitory peptide was screened. The results showed that HP20SS macroporous resin was the best for the separation and purification of ACE inhibitory peptide. Under the conditions of 10.0 mg/mL of hydrolysate, 2.0 BV/h of sample loading, 3 h of standing adsorption, 70% ethanol solution of eluent, 1.0 mL/min of eluent, after enrichment, the molecular weight of ACE inhibitory peptide was 2.65×10³ Da, the purity was 89.16%, and the inhibition rate was up to 92.18%, the IC₅₀ value was 1.02 mg/mL. The average recovery was 94.76% and RSD was 0.63% after three parallel tests. Comprehensive analysis showed that HP20SS macroporous resin had a good separation and purification effect on the ACE inhibitory peptide of jellyfish, and the process was reasonable and feasible with good reproducibility.