In this study, rotten strawberries were used as carbon precursor to prepare nitrogen-doped porous biocarbons for CO2 capture. The sorbents were synthesized by hydrothermal treatment of rotten strawberries, followed by KOH activation. The nitrogen in the resulting sorbents is inherited from the rotten strawberry precursor. This series of samples demonstrates high CO2 uptake at 1 bar, up to 4.49 mmol g(1) at 25 degrees C and 6.35 mmol g(1) at 0 degrees C. In addition to narrow micropore volume and nitrogen content, the pore size of narrow micropores also plays a key role in determining the CO2 capture capacity under ambient conditions. Furthermore, these sorbents possess stable reusability, moderate heat of CO2 adsorption, quick CO2 adsorption kinetics, reasonable CO2/N-2 selectivity, and high dynamic CO2 capture capacity under simulated flue gas conditions. All these merits along with the zero-cost and wide availability of rotten strawberry precursor make this type of sorbent highly promising in CO2 capture from combustion flue gas.