This study extracted peptidoglycan (PG) from Lactobacillus plantarum ATCC8014, its acrylamide (AA) adsorption behavior was evaluated by creating adsorption models, and its binding characterizations were investigated by physicochemical methods. The kinetics and isothermal model revealed that the biosorption of AA by PG conformed to Langmuir, Freundlich equations, and the second-order kinetic model, confirming that the adsorption process involved both physisorption and chemisorption. Fourier transform infrared spectroscopy and chemical blocking of functional groups confirmed that carboxyl, amino and hydroxyl groups were involved. Meanwhile, a new peak was generated in the proton nuclear magnetic resonance spectrum of PG upon adsorption, and the water contact angle was significantly reduced, indicating that hydrogen bonds and hydrophobic force were involved in the biosorption. Besides, energy dispersive spectroscopy and X-ray photoelectron spectroscopy results have important findings, suggesting that amide bonds might be formed during the adsorption process. Subsequently, this speculation was confirmed by the identification results of amidase. Overall, our results indicated that the mechanism of adsorption is complex and involves hydrogen bonding, hydrophobic forces and the formation of chemical bonds. Display omitted •Peptidoglycan has the ability to biosorb acrylamide.•Physisorption and chemisorption are involved in the adsorption process.•The amino, carboxyl and hydroxyl groups are involved in the adsorption.•Adsorption involves hydrogen bonds, hydrophobic forces and form amide bonds.