Abstract: For the study on flexural performance of a RC slab strengthened with prestressed AFRP sheets,the flexural experiments on 8 RC slabs with the same reinforcement ratio but different strengthening parameters was carried out.The variable paramerers were the consumed magnitude and the prestressing level of AFRP sheets.Based on the experiment,the slabs strengthened with prestressed AFRP sheets were compared with the slabs strengthened with non-prestressed AFRP sheets on the properties of cracking load,yield load,ultimate load,flexural rigidity,and ductility.Results show that the prestressed AFRP sheets greatly improve the cracking load,yield load,and ultimate load compared to unstrenghened RC slabs,and greatly improve the cracking load compared to RC slabs with unprestressed AFRP sheets.The strengthening effect is more obvious with increasing prestressing level and consumed magnitude of AFRP sheets.Finally,the calculation of load-carring capacity is performed and in good agreement with the experimental results.