The mechanisms of pectin oligosaccharides H1 （POS_H1） regulating cholesterol metabolism based on the efflux，uptake and synthesis of cholesterol were studied using the macrophage model. Results showed that POS_H1 and their microbiota fermentation metabolites （P24） promoted the efflux of cholesterol via increasing protein expressions of key genes in the liver X receptor-α-ATP-binding cassette transporter （ABC） A1/ ABCG1 pathway. Microbial degradation made POS_H1 capable of inhibiting protein expressions of scavenger receptor A and cluster differentiating 36 to suppress cholesterol uptake，while POS_H1 could not. Both POS_H1 and P24 downregulated 3-hydroxy-3-methylglutaryl coenzyme-A reductase at protein expression levels to inhibit cholesterol synthesis. It is indicated that POS_H1 regulates cholesterol metabolism by promoting the efflux of cholesterol，inhibiting the uptake and synthesis of cholesterol，which is one of the mechanisms by which POS_H1 regulates cholesterol metabolism，and this mechanism is related to the fermentation of POS_H1 by gut microbiota.