In the present study,four components of apple pectins: water-soluble pectin(WSP),chelate-soluble pectin(CSP),acid-soluble pectin(ASP) and base-soluble pectin(BSP),were extracted from apple peel by water,0.5% ammonium oxalate,0.05 mol / L HCl and 1 mol / L KOH,respectively.Their physicochemical properties,including monosaccharide composition with corresponding molar ratio,sugar content,uronic acid content,protein content,relative molecular weight and FTIR spectra were investigated.Their in vitro inhibitory effects on the growth of HT-29 cells were preliminarily investigated.As a result,it was found that all the four pectin polysaccharides,WSP,CSP,ASP and BSP pssessed a relative molecular weight over 4.0 × 105Da.CSP contains the most amount of galacturonic acids,while BSP had the most glucose without galacturonic acids.Meanwhile,all four pectin polysaccharides showed inhibitory activities against the proliferation of HT-29 cells,of which CSP had the highest activity and BSP had the lowest.The difference among four pectin polysaccharides in the inhibitory activity against HT-29 cells may due to their different contents of galactose and galacturonic acid.